Polyethylene resin by Ziegler-Natta catalyst and film incorporating the same

Abstract

Embodiments of the present disclosure specifically relate to LLDPE compositions produced from heterogeneous procatalyst compositions, and blown and cast films incorporating these LLDPE compositions.

Description

Technical Field

[0001] Cross - Reference to Related Applications This application claims priority to U.S. Provisional Patent Application No. 62 / 855,418, filed on May 31, 2019, the entire disclosure of which is incorporated herein by reference.

[0002] Embodiments of the present disclosure generally relate to linear low - density polyethylene (LLDPE) compositions, and more particularly to LLDPE compositions produced from heterogeneous procatalyst compositions and films incorporating these LLDPE compositions.

Background Art

[0003] Olefin polymers such as ethylene polymers and propylene polymers are produced using various catalysts. The components of such catalysts used in the polymerization process of olefin polymers are important factors contributing to the characteristics and properties of such olefin polymers.

[0004] Ethylene polymers are manufactured for use in a wide variety of articles. The polyethylene polymerization process can be varied in many respects to produce a wide variety of polyethylene resins having various physical properties suitable for use in various applications. Hydrogen can also be added to the reactor. Catalysts for producing ethylene polymers can typically include chromium - based catalysts, Ziegler - Natta catalysts, and / or molecular (either metallocene or non - metallocene) catalysts. Periodically or continuously, a portion of the reaction mixture, including the formed polyethylene product, is removed from the reactor along with unreacted ethylene and any one or more comonomers. The reaction mixture when removed from the reactor can be processed to remove the polyethylene product from the unreacted reactants, and the unreacted reactants are typically recycled back into the reactor. Alternatively, the reaction mixture can be sent to a second reactor connected in series with the first reactor, where a second polyethylene fraction can be produced.

[0005] Conventional polymers produced by Ziegler-Natta catalysts generally contain a relatively large amount of high-density fraction relative to the molecular catalyst. This high-density fraction prevents the polymer from achieving the optical and abuse properties required in some applications. Therefore, there is a need for polymers with a reduced high-density fraction to enable improvement of optical and abuse properties such as dart impact without suffering a significant trade-off in mechanical strength and tear properties. SUMMARY OF THE INVENTION

[0006] This embodiment meets these requirements by producing a LLDPE polymer having a reduced high-density fraction and improved optical and abuse properties without a significant trade-off in mechanical strength and tear properties.

[0007] According to one embodiment of the present disclosure, an inflation film comprising a linear low density polyethylene (LLDPE) polymer is provided. The LLDPE is a polymerization reaction product of an ethylene monomer and a C3-C 12 ethylene comonomer. The LLDPE has a density of 0.904 to 0.925 g / cc and a melt index (I2) of 0.5 to 1.5 g / 10 minutes as measured according to ASTM 1238 under a load of 2.16 kg at a temperature of 190 °C. 、 I 10It has a melt flow ratio (I10 / I2) of 6.5 - 7.6 measured in accordance with ASTM 1238 at a temperature of 190 °C under a load of 10 kg, and a molecular weight distribution (MWD = Mw / Mn) of 2.5 - 3.6 when measured by gel permeation chromatography. LLDPE is a copolymer fraction exceeding 85%, defined as the ratio of the mass eluted at a temperature above 35 °C and below 95 °C to the total eluted mass when measured using an improved comonomer content distribution (iCCD) curve of elution mass versus temperature, a high-density fraction of 0.5 - 8.0%, defined as the ratio of the mass eluted at a temperature of 95 °C or higher to the total mass, and a soluble fraction of 1.0% - 12.0%, defined as the ratio of the mass eluted at a temperature of 35 °C or lower to the total mass, and includes a short-chain branch distribution defined thereby.

[0008] According to another embodiment of the present disclosure, a linear low-density polyethylene (LLDPE) polymer is provided. LLDPE comprises a polymerization reaction product of an ethylene monomer and a C3-C 12 ethylene comonomer. LLDPE has a density of about 0.910 - 0.920 g / cc, a melt index (I2) of 2.0 - 7.0 g / 10 min when measured in accordance with ASTM 1238 under a load of 2.16 kg at a temperature of 190 °C, and a melt flow ratio (I10 / I2) of 6.5 - 7.5 where I10 is measured in accordance with ASTM 1238 at a temperature of 190 °C under a load of 10 kg. LLDPE has a high-density fraction of 0.5 - 6.0%, defined as the ratio of the mass eluted within a temperature range of 95 °C or higher to the total eluted mass when measured using an iCCD curve of elution mass versus temperature, a soluble fraction of 1.0 - 3.0%, defined as the ratio of the mass eluted within a temperature range of 35 °C or lower to the total eluted mass, the ratio of the soluble fraction to the high-density fraction being 0.40 - 0.65, and the maximum elution peak height occurring at a temperature exceeding 80 °C, and includes a short-chain branch distribution defined thereby. In a further embodiment, LLDPE may be included in a cast film.

Embodiments for Carrying Out the Invention

[0009] Here, specific embodiments of the present application will be described. However, the present disclosure may be embodied in different forms and should not be construed as being limited to the embodiments described in the present disclosure. Rather, 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] Definitions The term "polymer" refers to a polymer compound prepared by polymerizing monomers, regardless of the same or different types of monomers. Thus, the general term "polymer" encompasses the terms "homopolymer" and "copolymer" or "interpolymer". A homopolymer is usually used to refer to a polymer prepared from only one type of monomer. Copolymers and interpolymers are usually used to refer to polymers prepared from two or more different monomers. Thus, the general terms "copolymer" and "interpolymer" include polymers prepared from three or more different types of monomers such as terpolymers.

[0011] "Polyethylene" or "ethylene-based polymer" shall mean a polymer containing units derived from ethylene monomers in an amount exceeding 50 mol%. This includes polyethylene homopolymers or copolymers (meaning units derived from two or more comonomers). General forms of polyethylene known in the art include low density polyethylene (LDPE), linear low density polyethylene (LLDPE), ultra low density polyethylene (ULDPE), very low density polyethylene (VLDPE), single site catalyst linear low density polyethylene (m-LLDPE) including both linear and substantially linear low density resins, medium density polyethylene (MDPE), and high density polyethylene (HDPE).

[0012] The term "LDPE" is sometimes also referred to as "high-pressure ethylene polymer" or "highly branched polyethylene", and is defined to mean that the polymer is partially or completely homopolymerized or copolymerized in an autoclave or tubular reactor at a pressure exceeding 14,500 psi (100 MPa) by using a free radical initiator such as a peroxide (see, for example, U.S. Patent No. 8,916,667, U.S. Patent No. 8,871,887, U.S. Patent No. 8,822,601, U.S. Patent No. 9,228,036, and U.S. Patent No. 9,765,160, which are incorporated herein by reference). LDPE resins typically have a density in the range of 0.915 - 0.935 g / cm 3 .

[0013] The term "LLDPE" includes resins made using Ziegler-Natta catalyst systems, and resins made using single-site catalysts including, but not limited to, bis-metallocene catalysts (sometimes called "m-LLDPE" or metallocene-LLDPE) and constrained geometry catalysts, and resins made using post-metallocene molecular catalysts. LLDPE includes linear, substantially linear, or non-uniform polyethylene copolymers or homopolymers. LLDPE contains less chain branching than LDPE and includes substantially linear ethylene polymers further defined in U.S. Patent No. 5,272,236, U.S. Patent No. 5,278,272, U.S. Patent No. 5,582,923, and U.S. Patent No. 5,773,155, uniformly branched linear ethylene polymer compositions such as those in U.S. Patent No. 3,645,992, non-uniformly branched ethylene polymers prepared according to the process disclosed in U.S. Patent No. 4,076,698, and / or blends thereof (such as those disclosed in US3,914,342). LLDPE resins can be made by gas phase, liquid phase, or slurry polymerization, or any combination thereof, using any type of reactor or reactor configuration known in the art.

[0014] The term "MDPE" refers to polyethylene having a density of 0.926 to 0.945 g / cc. "MDPE" is typically made using a chromium or Ziegler-Natta catalyst, or, without limitation, using single-site catalysts including bis-metallocene catalysts and constrained geometry catalysts.

[0015] The term "HDPE" refers to polyethylene having a density greater than about 0.945 g / cc, which are generally prepared with Ziegler-Natta catalysts, chromium catalysts, or, without limitation, single-site catalysts including bis-metallocene catalysts and constrained geometry catalysts.

[0016] The term "ULDPE" refers to polyethylene having a density of 0.880 to 0.909 g / cc, which are generally prepared with Ziegler-Natta catalysts, without limitation, single-site catalysts including bis-metallocene catalysts and constrained geometry catalysts, and post-metallocene molecular catalysts. As used herein, the term "propylene-based polymer" refers to a polymer that contains, in polymerized form, more than 50% by weight of units derived from propylene monomers. This includes propylene homopolymers, random copolymer polypropylenes, impact copolymer polypropylenes, propylene / alpha-olefin interpolymers, and propylene / alpha-olefin copolymers. These polypropylene materials are generally known to those skilled in the art.

[0017] "Multi-layer film" means any structure having a plurality of layers. For example, the multi-layer structure may have 2, 3, 4, 5, or more layers. The multi-layer film can be described as having layers designated by letters. For example, a three-layer structure having a core layer B and two outer layers A and C may be designated as A / B / C. Similarly, a structure having two core layers B and C and two outer layers A and D may be designated as A / B / C / D. Furthermore, those skilled in the art will know that additional layers E, F, G, etc. can also be incorporated into this structure.

[0018] Description of Catalyst The term "pre-catalyst" refers to a compound that has catalytic activity when combined with an activator. The term "activator" refers to a compound that chemically reacts with the pre-catalyst to convert the pre-catalyst into a catalytically active catalyst. As used herein, the terms "promoter" and "activator" are interchangeable terms.

[0019] When used to describe a particular carbon atom-containing chemical group, the bracketed expression in the form of "(C x -C y )" means that the unsubstituted form of the chemical group has from x to y carbon atoms including x and y. For example, (C1-C 50 )alkyl is an alkyl group having 1 to 50 carbon atoms in its unsubstituted form. In some embodiments and general structures, a particular chemical group may be substituted by one or more substituents such as R S .

[0020] The term "(C1-C 50 )hydrocarbyl" means a hydrocarbon radical having 1 to 50 carbon atoms, wherein each hydrocarbon radical is aromatic or non-aromatic, saturated or unsaturated, straight-chain or branched-chain, cyclic (having 3 or more carbon atoms, including monocyclic and polycyclic, fused and non-fused polycyclic, and bicyclic) or acyclic, and is substituted or unsubstituted by one or more R S .

[0021] In the present disclosure, (C1-C 50 )hydrocarbyl can be unsubstituted or substituted (C1-C 50 )alkyl, (C3-C 50 )cycloalkyl, (C3-C 20 )cycloalkyl-(C1-C 20 )alkylene, (C6-C 40 )aryl, or (C6-C 20 )aryl-(C1-C 20 )alkylene (such as benzyl (-CH2-C6H5)).

[0022] “(C1-C 50 )alkyl” and “(C1-C 18 )alkyl” terms mean a saturated straight-chain or branched hydrocarbon radical having 1 to 50 carbon atoms and a saturated straight-chain or branched hydrocarbon radical having 1 to 18 carbon atoms, respectively, which are unsubstituted or substituted by one or more R S . Examples of unsubstituted (C1-C 50 )alkyl are unsubstituted (C1-C 20 )alkyl, unsubstituted (C1-C 10 )alkyl, unsubstituted (C1-C5)alkyl, methyl, ethyl, 1-propyl, 2-propyl, 1-butyl, 2-butyl, 2-methylpropyl, 1,1-dimethylethyl, 1-pentyl, 1-hexyl, 1-heptyl, 1-nonyl, and 1-decyl. Examples of substituted (C1-C 40 )alkyl are substituted (C1-C 20 )alkyl, substituted (C1-C 10 )alkyl, trifluoromethyl, and [C 45 alkyl. The term “[C 45 alkyl” means that up to 45 carbon atoms are present in the radical containing the substituent, for example, (C S -C 27 -C 40 )alkyl substituted by one R S which is (C1-C5)alkyl respectively. Each (C1-C5)alkyl can be methyl, trifluoromethyl, ethyl, 1-propyl, 1-methylethyl, or 1,1-dimethylethyl.

[0023] The term “(C6-C 50 )aryl” means an unsubstituted or (one or more R Smeans a monocyclic, bicyclic, or tricyclic aromatic hydrocarbon radical substituted by), where at least 6 to 14 of the carbon atoms are aromatic ring carbon atoms. A monocyclic aromatic hydrocarbon radical contains one aromatic ring, a bicyclic aromatic hydrocarbon radical has two rings, and a tricyclic aromatic hydrocarbon radical has three rings. When a bicyclic or tricyclic aromatic hydrocarbon radical is present, at least one of the rings of the radical is aromatic. The other one or more rings of the aromatic radical can independently be fused or unfused, aromatic or non-aromatic. Unsubstituted (C6-C 50 ) Examples of aryl include unsubstituted (C6-C 20 ) aryl, unsubstituted (C6-C 18 ) aryl, 2-(C1-C5)alkyl-phenyl, phenyl, fluorenyl, tetrahydrofluorenyl, indacenyl, hexahydroindacenyl, indenyl, dihydroindenyl, naphthyl, tetrahydronaphthyl, and phenanthrene. Examples of substituted (C6-C 40 ) aryl include substituted (C1-C 20 ) aryl, substituted (C6-C 18 ) aryl, 2,4-bis([C 20 alkyl)-phenyl, polyfluorophenyl, pentafluorophenyl, and fluoren-9-one-1-yl.

[0024] The term “(C3-C 50 ) cycloalkyl” means a saturated cyclic hydrocarbon radical having 3 to 50 carbon atoms that is unsubstituted or substituted by one or more R S . Other cycloalkyl groups (e.g., (C x -C y ) cycloalkyl) are defined in a similar manner as those having x to y carbon atoms and being either unsubstituted or substituted by one or more R S . Examples of unsubstituted (C3-C 40 ) cycloalkyl are unsubstituted (C3-C 20 ) cycloalkyl, unsubstituted (C3-C 10)It is cycloalkyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, and cyclodecyl. Substituted (C3-C 40 )Examples of cycloalkyl are substituted (C3-C 20 )cycloalkyl, substituted (C3-C 10 )cycloalkyl, cyclopentanone-2-yl, and 1-fluorocyclohexyl.

[0025] The term "halogen atom" or "halogen" means a radical of a fluorine atom (F), a chlorine atom (Cl), a bromine atom (Br), or an iodine atom (I). The term "halide" means the anionic form of a halogen atom of fluoride (F - ), chloride (Cl - ), bromide (Br - ) or iodide (I - ).

[0026] Ziegler-Natta catalysts typically include a procatalyst and a cocatalyst. The main components in a Ziegler-Natta procatalyst include a titanium species, a magnesium chloride (MgCl2) support, and optionally an electron donor. In some embodiments, a titanium precursor and a magnesium precursor are chlorinated and optionally converted to a Ziegler-Natta procatalyst using a chlorinating agent in the presence of an electron donor. In some embodiments, the magnesium chloride support is pre-prepared from a magnesium precursor, followed by introduction of the titanium species, which can undergo chlorination using a chlorinating agent. In some particular embodiments, the chlorination of the titanium species proceeds in the absence of an electron donor. In some particular embodiments, the chlorination of the titanium species proceeds in the presence of an electron donor. The magnesium chloride support can be prepared via chlorination of a magnesium compound. In some embodiments, the magnesium chloride support is prepared by chlorination of a solution of a hydrocarbon-soluble magnesium precursor to obtain a MgCl2 slurry in the same hydrocarbon solvent used to prepare the magnesium precursor solution. In some embodiments, the magnesium chloride support is prepared prior to introduction of other procatalyst components, and such a magnesium chloride support is also referred to as a pre-formed magnesium chloride support, e.g., a pre-formed MgCl2 slurry.

[0027] In some embodiments, a non-reducing hydrocarbon-soluble transition metal compound in a +2 or +3 oxidation state is used together with a titanium compound to make a Ziegler-Natta pro catalyst. In some embodiments, the Ziegler-Natta pro catalyst is made using an MgCl2 slurry pre-formed in the same hydrocarbon solvent used to make the magnesium precursor solution. In some embodiments, the non-reducing transition metal compound is soluble in the hydrocarbon solvent of the MgCl2 slurry. Without intending to be bound by any theory, it is believed that solubility in the hydrocarbon solvent of the MgCl2 slurry results in better dispersion of the transition metal compound in the slurry and promotes the interaction between the transition metal compound and the MgCl2 surface. In some embodiments, a chlorinating agent is also used in the synthesis of the Ziegler-Natta pro catalyst. In some embodiments, a pre-formed MgCl2 slurry, a titanium compound, a non-reducing hydrocarbon-soluble transition metal compound in a +2 or +3 oxidation state, and a chlorinating agent are used to make the Ziegler-Natta pro catalyst. The addition of the titanium compound, transition metal compound, and chlorinating agent to the MgCl2 slurry can be carried out simultaneously, together, or in any order (see Table 1 below) (if two or three materials are listed together, they are pre-mixed and added together or added simultaneously).

Table 1

[0028] The inventors have surprisingly found that by including a non-reducing hydrocarbon-soluble transition metal compound in the procatalyst in an oxidation state of +2 or +3, the polymer high density fraction in the resulting polyethylene copolymer is significantly reduced. Without wishing to be bound by theory, it is believed that the reaction between the transition metal compound and the chlorinating agent converts the transition metal compound into a species that is not soluble in hydrocarbons and deposits it on the surface of MgCl2, thus changing the nature of the interaction between the MgCl2 support and the active titanium species and resulting in a change in the polymer composition. Further unexpected improvements in polymer properties were also obtained from including a vanadium compound in the procatalyst. The vanadium compound can be introduced into the procatalyst simultaneously, together with, or in any order with the other procatalyst components.

[0029] In some embodiments, the chlorinating agent is added to MgCl2 before the other components. In some embodiments, less than 10% of the non-reducing hydrocarbon-soluble transition metal compound remains in the solution phase 30 minutes after being added to the MgCl2 treated with the chlorinating agent. In another embodiment, less than 5% of the non-reducing hydrocarbon-soluble transition metal compound remains in the solution phase 75 minutes after being added to the MgCl2 treated with the chlorinating agent.

[0030] The reaction temperatures for adding each procatalyst component to MgCl2 may be the same or different. In some embodiments, the reaction temperature can be selected from -30°C to 200°C, or 0°C to 100°C, or 20°C to 50°C.

[0031] The reaction times for adding each procatalyst component to MgCl2 may be the same or different. In some embodiments, the reaction time can be selected from 1 minute to 10 days, or 10 minutes to 24 hours, or 30 minutes to 12 hours.

[0032] Embodiments of the present disclosure include a heterogeneous procatalyst. The heterogeneous procatalyst includes a titanium species, a hydrocarbon-soluble transition metal compound having the structure M(OR 1 ) z and a structure A(Cl) x (R2 ) 3-x may contain a chlorinating agent having 3-x and a magnesium chloride component.

[0033] In the structure M(OR 1 ) z , M is a transition metal having an oxidation state of +2 or +3. The transition metal M may be non-reducing and may not contain Ti. The term "transition metal" refers to the elements of Groups 3-12 according to the IUPAC nomenclature and does not include lanthanide or actinide elements. In one or more embodiments, the transition metal M is selected from the transition metals of the first row (also referred to as the fourth period transition metals). In some embodiments, M is selected from zinc, copper, cobalt, manganese, iron, or chromium.

[0034] In a hydrocarbon-soluble transition metal compound, each R of M(OR 1 ) z may be independently selected from (C1-C 1 )hydrocarbyl or -C(O)R 30 ), wherein R 11 is (C1-C 11 )hydrocarbyl. The subscript z of M(OR 30 ) 1 ) z is 2 or 3. The transition metal compound is soluble in a hydrocarbon solvent. In one or more embodiments, each R 1 and R 11 may optionally be substituted with one or more halogen atoms or one or more -Si(R S )3, wherein each R S is (C1-C 30 )hydrocarbyl. In some embodiments, R 1 and R 11 may be selected from methyl, ethyl, propyl, 2-propyl, n-butyl, tert-butyl, isobutyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, 2-ethylhexyl, tert-octyl, n-nonyl, or n-decyl. In some embodiments, R 1 is -C(O)R 11When it is, R 11 may be selected from 3-heptyl and 2-methyloctan-2-yl. In one or more embodiments, the hydrocarbon-soluble transition metal compound may be a metal salt of naphthenic acid. Naphthenic acid is a mixture of alicyclic carboxylic acids and can be represented by the formula C n H 2(n-z) O2, where n is from 5 to 30 and z is from 0 to 4. In a non-limiting example, when the hydrocarbon-soluble transition metal compound is a metal salt of naphthenic acid, R 1 is -C(O)R 11 , and R 11 may be (3-ethyl)-2-cyclopentyl-2-ethyl. Naphthenic acid can be isolated from crude oil.

[0035] In some embodiments, when R 1 or R 11 of the transition metal compound is substituted with one or more -Si(R S )3 groups, R S may be selected from methyl, ethyl, n-propyl, 2-propyl, n-butyl, tert-butyl, isobutyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, 2-ethylhexyl, tert-octyl, n-nonyl, or n-decyl. In some embodiments, when R 1 is -C(O)R 11 , R 11 may be selected from 3-heptyl and 2-methyloctan-2-yl.

[0036] In some embodiments, the transition metal compound is a metal alkoxide or carboxylate having a melting point of 50 °C or lower, preferably 35 °C or lower, and most preferably 25 °C or lower. In some embodiments, the transition metal compound M(OR 1 ) z or M(OC(O)R 11 ) z is at the 2-position of the R 1 or R 11 group (C1-C 10) It contains a hydrocarbyl substitution. In one or more embodiments, M is selected from zinc, cobalt, copper, manganese, iron, or chromium. In some embodiments, the transition metal compound is zinc(II) 2-ethylhexanoate, zinc(II) neodecanoate, zinc(II) naphthenate, cobalt(II) 2-ethylhexanoate, cobalt(II) neodecanoate, cobalt(II) naphthenate, copper(II) 2-ethylhexanoate, copper(II) neodecanoate, copper(II) naphthenate, manganese(II) 2-ethylhexanoate, manganese(II) neodecanoate, manganese(II) naphthenate, iron(III) 2-ethylhexanoate, iron(III) neodecanoate, iron(II) naphthenate, iron(III) ethoxide, chromium(III) 2-ethylhexanoate, chromium(III) neodecanoate, or chromium(III) naphthenate.

[0037] The structure A(Cl) of the chlorinating agent x (R 2 ) 3-x where A is aluminum or boron, and R 2 is (C1-C 30 ) hydrocarbyl, and the subscript x is 1, 2, or 3. In one or more embodiments, the subscript x is 2, and R 2 is selected from methyl, ethyl, n-propyl, 2-propyl, n-butyl, tert-butyl, isobutyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, tert-octyl, n-nonyl, or n-decyl. In some embodiments, the subscript x is 3.

[0038] In some embodiments, the chlorinating agent can be selected from aluminum trichloride, methylaluminum dichloride, dimethylaluminum chloride, ethylaluminum dichloride, diethylaluminum chloride, ethylaluminum sesquichloride, isobutylaluminum dichloride, diisobutylaluminum chloride, n-hexylaluminum dichloride, di-n-hexylaluminum chloride, n-octylaluminum dichloride, di-n-octylaluminum chloride, boron trichloride, phenylboron dichloride, dicyclohexylboron chloride, silicon tetrachloride, methyltrichlorosilane, dimethyldichlorosilane, chlorotrimethylsilane, ethyltrichlorosilane, dichlorodiethylsilane, chlorotriethylsilane, n-propyltrichlorosilane, dichlorodi(n-propyl)silane, chlorotri(n-propyl)silane, isopropyltrichlorosilane, dichlorodiisopropylsilane, chlorotriisopropylsilane, n-butyltrichlorosilane, dichlorodi(n-butyl)silane, chlorotri(n-butyl)silane, isobutyltrichlorosilane, dichlorodiisobutylsilane, chlorotriisobutylsilane, cyclopentyltrichlorosilane, dichlorodicyclopentylsilane, n-hexyltrichlorosilane, cyclohexyltrichlorosilane, dichlorodicyclohexylsilane, and combinations thereof.

[0039] In one or more embodiments, the heterogeneous procatalyst further contains a vanadium component. The vanadium species can be selected from VX4, VOX3, or VO(OR 3 )3, wherein each X is independently a halogen atom or a (C1-C 40 ) heterohydrocarbyl, R 3 is a (C1-C 20 ) hydrocarbyl or -C(O)R 31 , and R 31 is a (C1-C 30 ) hydrocarbyl. In one or more embodiments, R 3 and R 31may be selected from methyl, ethyl, n-propyl, 2-propyl, n-butyl, tert-butyl, isobutyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, tert-octyl, n-nonyl, or n-decyl. In some embodiments, R 1 when is -C(O)R 31 , R 31 is 3-heptyl.

[0040] In some embodiments, the vanadium component is selected from vanadium(IV) chloride, vanadium(V) oxytrichloride, vanadium(V) oxytriethoxide, vanadium(V) oxytripropoxide, vanadium(V) oxytriisopropoxide, vanadium(V) oxytributoxide, vanadium(V) oxytriisobutoxide, vanadyl acetate, vanadium(IV) oxide stearate, vanadium octoate, and combinations thereof.

[0041] In an embodiment, the polymerization process of the ethylene-based polymer comprises contacting ethylene, optionally with one or more α-olefins, in the presence of a catalyst system, the catalyst system comprising one heterogeneous procatalyst or two or more heterogeneous procatalysts.

[0042] In an embodiment, the process for generating the heterogeneous procatalyst comprises forming magnesium chloride (MgCl2) as a MgCl2 slurry in a hydrocarbon solvent. Then, a chlorinating agent, a transition metal compound, and a titanium species are mixed in the MgCl2 slurry, wherein the transition metal compound has the structure M(OR 1 ) z , and the chlorinating agent has the structure A(Cl) x (R 2 ) 3-x .

[0043] In one or more embodiments of the heterogeneous catalyst, the magnesium chloride component has a surface area of 100 m 2It has a surface area of 150 m 2 / g or more, or 200 m 2 / g or more. In other embodiments, the magnesium chloride component has a surface area of 100 m 2 / g to 800 m 2 / g, or 200 m 2 / g to 600 m 2 / g, or 300 m 2 / g to 500 m 2 / g.

[0044] In one or more embodiments, magnesium chloride includes a high surface area that can be obtained from chlorination of a magnesium compound. Such magnesium compounds include organomagnesium, organomagnesium halides, magnesium alkoxides, magnesium alkoxide carbonates, magnesium carboxylates, and combinations thereof. In embodiments, magnesium chloride can be obtained from the conversion of a magnesium chloride adduct. Suitable magnesium chloride adducts include magnesium chloride adducts with alcohols and magnesium chloride adducts with ethers. In some embodiments, the magnesium chloride adduct is a magnesium chloride adduct with ethanol. In some embodiments, the magnesium chloride adduct is a magnesium chloride adduct with tetrahydrofuran.

[0045] In one or more embodiments, the magnesium chloride component includes, for example, the reaction product of a chloride source with a hydrocarbon-soluble hydrocarbylmagnesium compound, or a mixture of compounds. Exemplary organomagnesium compounds include di(C1-C 20 )alkylmagnesium or di(C1-C 20)Aryl magnesium compounds, especially di(n-butyl)magnesium, di(sec-butyl)magnesium, diisopropylmagnesium, di-n-hexylmagnesium, isopropyl-n-butyl-magnesium, ethyl-n-hexylmagnesium, ethyl-n-butylmagnesium, di-n-octylmagnesium, and combinations thereof. Exemplary suitable magnesium diaryls include diphenylmagnesium, dibenzylmagnesium, and ditolylmagnesium. The organomagnesium compound can optionally be treated with an organoaluminum compound to improve solubility, reduce solution viscosity, or improve solubility and reduce solution viscosity. Stabilizers may also be present, including those derived from substituted phenol compounds. Additional suitable organomagnesium compounds include alkyl and aryl magnesium alkoxides, aryloxides and chlorides, and mixtures of the foregoing. A very preferred organomagnesium compound is a halogen-free organomagnesium compound.

[0046] Among the chloride sources that can be used in the preparation of the magnesium chloride component for use herein are organic chlorides and metal and non-metal chlorides containing hydrogen chloride. Suitable metal chlorides that can be used herein include MR y-a Cl a having the formula wherein M is a metal of Group 13, 14 or 15 of the Periodic Table, R is a monovalent organic radical, y has a value corresponding to the valence of M, and a has a value from 1 to y.

[0047] In one or more embodiments, the metal chloride can be selected from alkylaluminum chlorides having the formula AlR 3-a Cl a wherein each R is independently (C1-C 10)It is a hydrocarbyl, preferably (C1-C6) alkyl, and a is a number from 1 to 3. Examples of alkylaluminum chloride include, but are not limited to, sesquiethylaluminum chloride, diethylaluminum chloride, and ethylaluminum dichloride, with ethylaluminum dichloride being particularly preferred. Alternatively, metal chlorides such as aluminum trichloride, or combinations of aluminum trichloride with alkylaluminum chloride or trialkylaluminum compounds can be suitably used.

[0048] Suitable non-metal chlorides and organic chlorides are of the formula R’Cl r represented by the formula, where R’ is hydrogen, (C1-C 10 ) hydrocarbyl, or a non-metal such as Si, P, Ga, or Ge, and the subscript r is an integer from 1 to 6. Particularly suitable chloride sources include, for example, hydrogen chloride, as well as t-alkyl chloride, sec-alkyl chloride, allyl chloride, and benzyl chloride, and other active hydrocarbyl chlorides such as these, where the hydrocarbyl is as defined previously herein. Active organic chlorides mean hydrocarbyl chlorides containing unstable chlorides that are at least as active, i.e., easily lost to another compound, such as the chloride of sec-butyl chloride, preferably as active as t-butyl chloride. In addition to organic monochlorides, organic dichlorides, trichlorides, and other poly-chlorides that are active as defined previously herein are also considered to be suitably used. Examples of preferred chloride sources include hydrogen chloride, t-butyl chloride, t-amyl chloride, allyl chloride, benzyl chloride, crotyl chloride, and diphenylmethyl chloride. Most preferred are hydrogen chloride, t-butyl chloride, allyl chloride, and benzyl chloride.

[0049] In some embodiments, the chloride compound can be hydrochloric acid gas. In embodiments, the organomagnesium compound and the chloride compound can be contacted at a temperature of -25°C to 100°C, or 0°C to 50°C. In some embodiments, heat removal is required to control the set reaction temperature within ±5°C, for example within ±3°C. In some embodiments, the amount of the chloride source is controlled to achieve a target molar ratio of Cl to Mg in the resulting MgCl2. For example, the molar ratio of Cl to Mg can be 1.8 to 2.0 in the case of a MgCl2 support lacking chloride, and 2.0 to 2.2 in the case of a MgCl2 support containing a large amount of chloride. In some embodiments, the slurry of the organomagnesium compound and the metal or non-metal chloride can be contacted for a time of 1 hour to 12 hours, or 4 hours to 6 hours. The concentration of the organomagnesium compound in the slurry (i.e., before the chloride compound is added to the slurry) can be sufficient such that when the chloride compound is added to the slurry, the resulting composition can contain a magnesium concentration of 0.005 moles per liter (mol / L) to 1.000 mol / L per liter.

[0050] In some embodiments, the MgCl2 slurry is prepared before being treated with other procatalyst components and is referred to herein as a "pre-formed MgCl2 slurry". In some embodiments, the MgCl2 slurry can have a concentration of MgCl2 of 0.005 mol / L to 10.00 mol / L, or 0.05 mol / L to 1.00 mol / L.

[0051] The magnesium chloride support can be pre-formed from an organomagnesium compound and a chloride source and stored for later use, or it can be pre-formed in situ, in which case the procatalyst is preferably prepared by mixing (1) an organomagnesium component and (2) a chloride source, followed by other procatalyst components, in a suitable solvent or reaction medium.

[0052] In one or more embodiments, the titanium species can be a titanium species having catalytic activity. In some embodiments, the titanium species is TiCl 4-c (OR)c or TiCl 3-d (OR) d wherein R is (C1-C 20 ) hydrocarbyl, c is 0, 1, 2, 3, or 4, and d is 0, 1, 2, or 3. For example, in some embodiments, the titanium species is titanium(IV) chloride, titanium(III) chloride, tris(2,2,6,6-tetramethyl-3,5-heptanedionato)titanium(III), trichlorotris(tetrahydrofuran)titanium(III), dichlorodi-n-butoxytitanium(IV), dichlorodiethoxytitanium(IV), dichlorodiisopropoxytitanium(IV), dichlorodiisobutoxytitanium(IV), chlorotriisopropoxytitanium(IV), chlorotri-n-butoxytitanium(IV), chlorotriisobutoxytitanium(IV), titanium(IV) tetraisopropoxide (Ti(O i Pr)4), titanium(IV) ethoxide, titanium(IV) n-butoxide, titanium(IV) isobutoxide, titanium(IV) 2-ethylhexoxide, dichlorobis(2,2,6,6-tetramethyl-3,5-heptanedionato)titanium(IV), tetrachlorobis(tetrahydrofuran)titanium(IV), methyltitanium(IV) chloride, or combinations thereof, but is not limited thereto. In some embodiments, the titanium species can be titanium(IV) tetrachloride or titanium(IV) tetraisopropoxide (Ti(O i Pr)4). For example, in some embodiments, the titanium species can include titanium halide, titanium alkoxide, or combinations thereof. For example, in some embodiments, examples of the titanium species include titanium(IV) chloride (TiCl4), titanium(IV) tetraisopropoxide (Ti(O i Pr)4), other titanium halides, or titanium alkoxides, or combinations thereof, but are not limited thereto.

[0053] In an embodiment, the process for preparing the heterogeneous procatalyst includes a hydrocarbon solvent. The hydrocarbon solvent is a non-halogenated (C3-C 30 ) alkyl or non-halogenated (C3-C 30) It can be selected from cycloalkyl solvents. In some embodiments, the hydrocarbon solvent may include an isoparaffin solvent. Examples of isoparaffin solvents include ISOPAR™ synthetic paraffin solvents available from ExxonMobil (e.g., ISOPAR™ E paraffin solvent), and special boiling point (SBP) solvents from Shell Chemicals (e.g., SBP 100 / 140 high purity dearomatized hydrocarbon solvent), but are not limited thereto. Other examples of hydrocarbon solvents include isobutane, pentane, isopentane, cyclopentane, hexane, 2-methylpentane, 3-methylpentane, cyclohexane, methylcyclopentane, heptane, 2-methylhexane, 3-methylhexane, octane, 2,2,4-trimethylpentane, tetradecane, and combinations thereof.

[0054] In one or more embodiments of the heterogeneous catalyst, the ratio of transition metal M (in the transition metal compound) to titanium is 0.1 to 10 (mol / mol). All individual values and subranges subsumed within "0.1 to 10 (mol / mol)" are disclosed herein as separate embodiments. For example, the range of "0.1 to 10 (mol / mol)" includes the subranges of 0.2 to 5, 0.5 to 3, and 0.3 to 2.

[0055] In one or more embodiments of the heterogeneous catalyst, the molar ratio of magnesium chloride to titanium is 1 to 100 (moles of magnesium chloride per mole of titanium metal). All individual values and subranges subsumed within "1 to 100" are disclosed herein as separate embodiments. For example, the range of "1 to 100" includes the subranges of 8.0 to 80, 15 to 50, and 30 to 70.

[0056] In one or more embodiments of the heterogeneous catalyst, the molar ratio of vanadium to titanium is 0.1 to 10 (moles of vanadium per mole of titanium metal). All individual values and subranges subsumed within "0.1 to 10" are disclosed herein as separate embodiments. For example, the range of "0.1 to 10 (mol / mol)" includes the subranges of 0.2 to 5, 0.5 to 3, and 0.3 to 4.

[0057] In some embodiments, a multi-metal pro-catalyst can be utilized as described in U.S. Patent No. 9,255,160, which is incorporated herein by reference. The multi-metal pro-catalyst used for the production of the reaction product is at least a ternary metal, but may also include more than three transition metals and can thus, in one embodiment, be more comprehensively defined as a multi-metal. These three or more transition metals are selected prior to the production of the catalyst. In certain embodiments, the multi-metal catalyst includes titanium as one element.

[0058] Promoter component The heterogeneous procatalyst according to the present disclosure can be combined with a cocatalyst to form a Ziegler-Natta catalyst. The Ziegler-Natta catalyst containing the heterogeneous procatalyst can be catalytically activated by any technique known in the art for activating Ziegler-Natta type procatalysts for olefin polymerization reactions. For example, the heterogeneous procatalyst can be catalytically activated by contacting the procatalyst with an activating cocatalyst or by combining the procatalyst with an activating cocatalyst. Suitable activating cocatalysts for use herein include alkylaluminums containing polymeric or oligomeric alumoxanes (also known as aluminoxanes). Combinations of one or more of the foregoing activating cocatalysts are also contemplated. The term "alkylaluminum" means monoalkylaluminum dihydride or monoalkylaluminum dihalide, dialkylaluminum hydride or dialkylaluminum halide, or trialkylaluminum. Examples of polymeric alumoxanes or oligomeric alumoxanes include methylalumoxane, triisobutylaluminum-modified methylalumoxane, and isobutylalumoxane. In some embodiments, the cocatalyst can be selected from alkyls of aluminum, haloalkyls of aluminum, halogenated alkylaluminums, and mixtures thereof. In some embodiments, the cocatalyst can be selected from triethylaluminum, trimethylaluminum, tri-n-butylaluminum, triisobutylaluminum, tri-n-hexylaluminum, tri-n-octylaluminum, diethylaluminum chloride, MAO, MMAO, diethylaluminum ethoxide, and mixtures thereof.

[0059] Ethylene-based polymer The catalyst systems described in the present disclosure can be utilized in the polymerization of olefins, mainly ethylene-based polymers. In some embodiments, only a single type of olefin or α-olefin is present in the polymerization scheme, producing a homopolymer. However, additional α-olefins may be incorporated into the polymerization procedure. The additional α-olefin comonomers typically have 20 or fewer carbon atoms. For example, the α-olefin comonomer can have 3 to 10 carbon atoms, or 3 to 8 carbon atoms. Exemplary α-olefin comonomers include, but are not limited to, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, and 4-methyl-1-pentene. For example, one or more α-olefin comonomers can be selected from the group consisting of propylene, 1-butene, 1-hexene, and 1-octene, or alternatively from the group consisting of 1-hexene and 1-octene.

[0060] Ethylene-based polymers, such as homopolymers and / or interpolymers (including copolymers) of ethylene, and optionally one or more comonomers such as α-olefins, can contain at least 50 mole percent (mol%) of monomer units derived from ethylene. All individual values and subranges subsumed within "from at least 50 mole percent" are disclosed herein as separate embodiments. For example, ethylene-based polymers, homopolymers and / or interpolymers (including copolymers) of ethylene, and optionally one or more comonomers such as α-olefins, can contain at least 60 mole percent of monomer units derived from ethylene, at least 70 mole percent of monomer units derived from ethylene, at least 80 mole percent of monomer units derived from ethylene, or 50 to 100 mole percent of monomer units derived from ethylene, or 80 to 100 mole percent of monomer units derived from ethylene.

[0061] In some embodiments, the catalyst system can produce an ethylene-based polymer that contains units of at least 90 mole percent derived from ethylene. All individual values and subranges from at least 90 mole percent are included herein and are disclosed herein as separate embodiments. For example, the ethylene-based polymer can contain units derived from ethylene of at least 93 mole percent, units of at least 96 mole percent, units derived from ethylene of at least 97 mole percent, or alternatively, units derived from ethylene of 90 to 100 mole percent, units derived from ethylene of 90 to 99.5 mole percent, or units derived from ethylene of 97 to 99.5 mole percent.

[0062] In some embodiments, the catalyst system produces an ethylene-based polymer having an amount of additional α-olefin that is less than 50 mole percent (mol%), and in other embodiments, the amount of additional α-olefin is at least 0.01 mol% to 25 mol%, and in further embodiments, the amount of additional α-olefin includes at least 0.1 mol% to 10 mol%. In some embodiments, the additional α-olefin is 1-octene or 1-hexane.

[0063] In the presence of a catalyst system comprising the heterogeneous procatalyst of the present disclosure, any conventional polymerization process can be used to produce an ethylene-based polymer. Such conventional polymerization processes include solution polymerization processes, gas phase polymerization processes, slurry phase polymerization processes, and any combination thereof that use one or more conventional reactors, such as loop reactors, isothermal reactors, fluidized bed gas phase reactors, stirred tank reactors, batch reactors, etc., in parallel, in series, or any combination thereof, but are not limited thereto. In one embodiment, the ethylene-based polymer can be produced by solution polymerization in a dual reactor system, such as a dual loop reactor system, where ethylene, and optionally one or more α-olefins, are polymerized in the presence of the catalyst system described herein and optionally one or more cocatalysts. The catalyst system described herein can optionally be used in the first reactor or the second reactor in combination with one or more other catalysts. In one embodiment, the ethylene-based polymer can be produced by solution polymerization in a dual reactor system, such as a dual loop reactor system, where ethylene, and optionally one or more α-olefins, are polymerized in both reactors in the presence of the catalyst system described herein.

[0064] In another embodiment, the ethylene-based polymer can be produced via solution polymerization in a single reactor system, such as a single loop reactor system or a single stirred tank reactor system, where ethylene and optionally one or more α-olefins are polymerized in the presence of a catalyst system as described in the present disclosure, optionally one or more cocatalysts as described in the previous paragraph, and optionally in combination with one or more other catalysts.

[0065] In the embodiments described herein, the ethylene-based polymer may have a metal catalyst residue of 1 part or more in total weight of at least ternary metal residues per 1 million parts of the polyethylene polymer. The at least ternary metal residues are selected from the group consisting of zinc, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, and combinations thereof, and each of the at least ternary metal residues is present in the range of 0.2 ppm or more, for example, 0.2 to 5 ppm. All individual values and sub-ranges from 0.2 ppm or more are included herein and disclosed herein. For example, the ethylene-based polymer can further contain at least 2 parts in total weight of at least ternary metal residues remaining from the multi-metal polymerization catalyst per 1 million parts of the polyethylene composition. In some embodiments, the ethylene-based polymer contains at least 0.75 ppm of V (vanadium). All individual values and sub-ranges from at least 0.75 ppm of V are included and disclosed herein. For example, the lower limit of V in the ethylene-based polymer can be 0.75, 1, 1.1, 1.2, 1.3, or 1.4 ppm, and the upper limit of V in the ethylene-based polymer can be 5, 4, 3, 2, 1.9, 1.8, 1.7, 1.6, 1.5, or 1 ppm.

[0066] The ethylene-based polymer may further contain one or more additives. Such additives include, but are not limited to, antistatic agents, color intensifiers, dyes, lubricants, pigments, primary antioxidants, secondary antioxidants, processing aids, ultraviolet stabilizers, and combinations thereof. The ethylene-based polymer may contain any amount of additives. The ethylene-based polymer may contain such additives in a total weight of about 0 to about 10 percent, based on the weight of the ethylene-based polymer and one or more additives. The ethylene-based polymer may further contain a filler, and examples of such filler include, but are not limited to, organic or inorganic fillers. The ethylene-based polymer may contain a filler in an amount of about 0 to about 20 weight percent, such as calcium carbonate, talc, or Mg(OH)2, based on the total weight of the ethylene-based polymer and all additives or fillers. The ethylene-based polymer can be further blended with one or more polymers to form a blend. In one or more embodiments, the additives, fillers, one or more polymers, or compounding agents may increase or decrease the density of the overall ethylene-based polymer.

[0067] The ethylene-based polymer may have a density of 0.850 g / cc to 0.970 g / cc according to ASTM D792 (incorporated herein by reference in its entirety). Further, the ethylene-based polymer may include LLDPE having a density of 0.904 to 0.925 g / cc, 0.904 to 0.920 g / cc, 0.910 to 0.920 g / cc, 0.916 to 0.920, 0.915 to 0.925, 0.917 to 0.923, or 0.912 to 0.918 g / cc. Further, the ethylene-based polymer may include LLDPE having a density of 0.930 to 0.970 g / cc, 0.931 to 0.965 g / cc, 0.932 to 0.950, 0.930 to 0.940, 0.950 to 0.970, or 0.933 to 0.940 g / cc. Further, the ethylene-based polymer may include LLDPE having a density of 0.915 to 0.930 g / cc, 0.916 to 0.929 g / cc, 0.917 to 0.928, or 0.918 to 0.927 g / cc.

[0068] In another embodiment, the ethylene polymer (e.g., LLDPE) has a melt index, I2, of 0.1 to 7.0 when measured according to ASTM D1238 (incorporated herein by reference in its entirety) at 190 °C and a load of 2.16 kg (Procedure D). For inflation film applications, the ethylene polymer can be LLDPE having a melt index (I2) of 0.5 to 2.5 g / 10 min, or 0.5 to 2.0 g / 10 min, or 1 g / 10 min or less. For cast film applications, the ethylene polymer can be LLDPE having a melt index (I2) of 2.0 to 7.0 g / 10 min, or 2.0 to 4.0 g / 10 min, or 2.5 to 3.5 g / 10 min.

[0069] Furthermore, the ethylene polymer can be LLDPE having a melt flow ratio (I 10 / I2) of 5 to 9, or 5 to 7.7, or 6.5 to 7.7, or 6.5 to 7.6, or 6.5 to 7.5, where I 10 is measured according to ASTM D1238 at 190 °C and a load of 10 kg (Procedure D).

[0070] In other embodiments, the LLDPE can have a molecular weight distribution (MWD) of 2.5 to 3.6 when measured by conventional gel permeation chromatography (GPC), where MWD is defined as M w / M n , M w being the weight average molecular weight and M n being the number average molecular weight. In further embodiments, the LLDPE has an MWD of 2.8 to 3.8. In further embodiments, the LLDPE has an MWD of 3.0 to 3.6. In further embodiments, the LLDPE has an MWD of 3.1 to 3.5. In further embodiments, the LLDPE has an MWD of 3.2 to 3.4.

[0071] Furthermore, the LLDPE includes a short chain branching distribution defined by an improved comonomer content distribution (iCCD) curve. In one embodiment, the LLDPE can have a high density fraction determined by an iCCD of 0.5 to 8.0%, and the high density fraction is defined as the ratio of the mass eluted at a temperature of 95° C. or higher to the total eluted mass. Optionally, the temperature range can be 95 to 115° C. In further embodiments, the LLDPE can have a high density fraction of 0.5 to 8.0%, 0.5 to 7.5%, or 3.0% to 8.0%.

[0072] Furthermore, the LLDPE can include a soluble or purge fraction determined by an iCCD of 0.5% to 12.0%, and the soluble fraction is defined as the ratio of the mass eluted at a temperature of 35° C. or lower to the total eluted mass. Optionally, the temperature range can be 23 to 35° C. In further embodiments, the soluble fraction is less than 5%. Furthermore, the soluble fraction is 0.5% to 5.0%, 0.5% to 4.0%, 0.5% to 3.0%, 0.5% to 2.0%, 0.5% to 1.0%, 1.0% to 5.0%, 1.0% to 4.0%, 1.0% to 3.0%, 1.0% to 2.0%, 2.0% to 5.0%, 2.0% to 4.0%, 2.0% to 3.0%, 3.0% to 5.0%, 3.0% to 4.0%, 4.0% to 5.0%.

[0073] Furthermore, the LLDPE can have a copolymer fraction of more than 85%, and the copolymer fraction is defined as the ratio of the mass eluted at a temperature above 35° C. and below 95° C. to the total eluted mass when measured using the iCCD curve of eluted mass versus temperature. In further embodiments, the copolymer fraction is more than 90%. In further embodiments, the copolymer fraction is more than 85% and less than 92%. In further embodiments, the ratio of the soluble fraction to the high density fraction is 0.4 to 0.65. Without being limited by theory, the improved properties discussed below are, in part, due to this larger copolymer fraction and smaller soluble and high density fractions.

[0074] Furthermore, the maximum elution peak height of LLDPE can occur at temperatures exceeding 80°C. In another embodiment, the maximum elution peak height of LLDPE can occur at temperatures below 90°C. In other words, the maximum elution peak height of LLDPE can occur at temperatures of 80 - 95°C or 80 - 90°C.

[0075] Inflation film The above ethylene-based polymer (e.g., LLDPE) can be incorporated into an inflation film. Various thicknesses are contemplated for the inflation film. In one embodiment, the inflation film can have a thickness of 0.3 mil to 10.0 mil, 0.3 mil to 9.0 mil, 0.3 mil to 8.0 mil, 0.3 mil to 7.0 mil, 0.3 mil to 6.0 mil, 0.3 mil to 5.0 mil, 0.3 mil to 4.0 mil, 0.3 mil to 3.0 mil, 0.3 mil to 2.0 mil, 0.3 mil to 1.0 mil, 1.0 mil to 10.0 mil, 1.0 mil to 9.0 mil, 1.0 mil to 8.0 mil, 1.0 mil to 7.0 mil, 1.0 mil to 6.0 mil, 1.0 mil to 5.0 mil, 1.0 mil to 4.0 mil, 1.0 mil to 3.0 mil, 1.0 mil to 2.0 mil, or any combination of thicknesses within these ranges.

[0076] Without being bound by theory, the above LLDPE provides an improved balance of optical properties (e.g., haze) and abuse resistance (e.g., dirt) due to the short-chain branch distribution defined by the above iCCD parameters, i.e., the soluble fraction, copolymer fraction, and high-density fraction.

[0077] In one embodiment, the inflation film can have a total haze (%) of 4.5% - 10.5% at a thickness of 2.0 mil, 5.4% - 10.2% at a thickness of 2.0 mil, or 7.0% - 10.0% at a thickness of 2.0 mil. Furthermore, the inflation film can have a dirt value of at least 900 g at a thickness of 2.0 mil and a resin density of less than 0.918 g / cc, and / or a dirt value of at least 600 g at a thickness of 2.0 mil, a melt index of less than 1.1 g / 10 min, and a resin density of less than 0.920 g / cc.

[0078] Various film configurations are contemplated for the inflation film. For example, the inflation film can be a multilayer film or a single-layer film. In embodiments, the number of layers of the inflation film can depend on several factors including, for example, the desired properties of the film, the desired thickness of the film, the content of other layers of the film, the end use of the film, the equipment available for manufacturing the film, and others. Multilayer inflation films can include up to 2, 3, 4, 5, 6, 7, 8, 9, 10, or 11 layers in various embodiments.

[0079] In some embodiments, the above ethylene-based polymer can be used in one or more layers of the film. In a single-layer film, the layer can, in various embodiments, comprise a polymer and a blend containing components selected from the above ethylene-based polymer, LLDPE, VLDPE (very low density polyethylene), MDPE, LDPE, HDPE, HMWHDPE (high molecular weight HDPE), propylene-based polymer, polyolefin plastomer (POP), polyolefin elastomer (POE), olefin block copolymer (OBC), ethylene vinyl acetate, ethylene acrylic acid, ethylene methacrylic acid, ethylene methyl acrylate, ethylene ethyl acrylate, ethylene butyl acrylate, isobutylene, maleic anhydride grafted polyolefin, any of the above ionomers, or combinations thereof. In a single-layer film, each layer can, in various embodiments, comprise a polymer and a blend containing components selected from the above ethylene-based polymer, LLDPE, VLDPE (very low density polyethylene), MDPE, LDPE, HDPE, HMWHDPE (high molecular weight HDPE), propylene-based polymer, polyolefin plastomer (POP), polyolefin elastomer (POE), olefin block copolymer (OBC), ethylene vinyl acetate, ethylene acrylic acid, ethylene methacrylic acid, ethylene methyl acrylate, ethylene ethyl acrylate, ethylene butyl acrylate, isobutylene, maleic anhydride grafted polyolefin, any of the above ionomers, or combinations thereof. In some embodiments, the multilayer film of the present disclosure can include one or more tie layers known to those skilled in the art.

[0080] In one embodiment, LLDPE is blended with LDPE. In one or more embodiments, an inflation film, which can be a single-layer or multilayer film, can comprise a blend having 50 to 95 wt% LLDPE, or 60 to 90 wt% LLDPE, or 70 to 85 wt% LLDPE. Conversely, the blend can comprise 5 to 50 wt% LDPE, or 10 to 40 wt% LDPE, or 15 to 30 wt% LDPE.

[0081] Cast film The above ethylene polymer (e.g., LLDPE) can also be incorporated into a cast film. Various thicknesses are contemplated for the cast film. In one embodiment, the cast film can have a thickness of 0.3 mil to 10.0 mil, 0.3 mil to 9.0 mil, 0.3 mil to 8.0 mil, 0.3 mil to 7.0 mil, 0.3 mil to 6.0 mil, 0.3 mil to 5.0 mil, 0.3 mil to 4.0 mil, 0.3 mil to 3.0 mil, 0.3 mil to 2.0 mil, 0.3 mil to 1.0 mil, 0.3 mil to 0.8 mil, 0.2 mil to 0.6 mil, 0.3 mil to 0.4 mil, 1.0 mil to 10.0 mil, 1.0 mil to 9.0 mil, 1.0 mil to 8.0 mil, 1.0 mil to 7.0 mil, 1.0 mil to 6.0 mil, 1.0 mil to 5.0 mil, 1.0 mil to 4.0 mil, 1.0 mil to 3.0 mil, 1.0 mil to 2.0 mil, or any combination of thicknesses within these ranges.

[0082] Without being bound by theory, the above LLDPE provides an improved balance of draw and puncture by the above iCCD parameters, i.e., the short chain branch distribution defined by the soluble fraction, copolymer fraction, and high density fraction. In one or more embodiments, the cast film has a highlight (200%) draw force of at least 50 lbf at a width of 20 inches and a thickness of 0.5 mil. Further, the cast film can have a pallet puncture resistance of at least about 14 lbf and a highlight ultimate draw of at least about 370% at a thickness of 0.5 mil.

[0083] In other embodiments, the cast film can have a pallet puncture resistance of at least 11 lbf and a highlight ultimate draw of at least 340% at a thickness of 0.7 mil. Further, the cast film can have a highlight (200%) draw force of at least 59 lbf at a width of 20 inches and a thickness of 0.7 mil.

[0084] Similar to inflation films, various film configurations are contemplated for cast films. For example, a cast film can be a multilayer film or a single-layer film. Further, a cast film can contain additional components such as ethylene-based polymers. The ethylene-based polymers described above can be used in two or more layers of the film in some embodiments. Other layers within the multilayer films of the present invention can, in various embodiments, be polymers selected from the ethylene-based polymers, LLDPE, VLDPE (very low density polyethylene), MDPE, LDPE, HDPE, HMWHDPE (high molecular weight HDPE), propylene-based polymers, polyolefin plastomers (POP), polyolefin elastomers (POE), olefin block copolymers (OBC), ethylene vinyl acetate, ethylene acrylic acid, ethylene methacrylic acid, ethylene methyl acrylate, ethylene ethyl acrylate, ethylene butyl acrylate, isobutylene, maleic anhydride grafted polyolefin, any of the aforementioned ionomers, or combinations thereof. In some embodiments, the multilayer films of the present disclosure can include one or more tie layers known to those skilled in the art. Some additional components or layers commonly used in the art can include other LLDPEs, amorphous hydrocarbons, and / or other LLDPEs blended with other substances known in the art as enhancing adhesion (''sticking'') to the pallet, polypropylene homopolymers, and polypropylene copolymers having polyethylene (but not limited to these).

[0085] In one embodiment, LLDPE is blended with LDPE. In one or more embodiments, a cast film, which can be a single-layer or multi-layer film, can include blends having 5 to 95 wt% LLDPE, 5 to 50 wt% LLDPE, 5 to 25 wt% LLDPE, 5 to 10 wt% LLDPE, 10 to 95 wt% LLDPE, 10 to 50 wt% LLDPE, 10 to 25 wt% LLDPE, 50 to 95 wt% LLDPE, 60 to 90 wt% LLDPE, or 70 to 85 wt% LLDPE. Conversely, the blend can include 5 to 50 wt% LDPE, 10 to 40 wt% LDPE, or 15 to 30 wt% LDPE.

[0086] Test method Density Samples for density measurement were prepared according to ASTM D 4703-10. The samples were pressed at 374°F (190°C) for 5 minutes at 10,000 psi (68 MPa). The temperature was maintained at 374°F (190°C) for the above 5 minutes, and then the pressure was increased to 30,000 psi (207 MPa) for 3 minutes. Subsequently, it was held at 70°F (21°C) and 30,000 psi (207 MPa) for 1 minute. Density measurements were performed within 1 hour of sample compression using ASTM D792-08, Method B.

[0087] Melt index (I2 and I 10 ) The melt index (MI) or I2 was measured according to ASTM D1238-13, Condition 190°C / 2.16 kg, Procedure D (multiple weighing procedure) and reported in grams eluted per 10 minutes (g / 10 min). I10 was measured using the same procedure under a 10 kg load condition and also reported in grams eluted per 10 minutes (g / 10 min).

[0088] Gel permeation chromatography (GPC) Regarding gel permeation chromatography (GPC), the chromatograph system consisted of a PolymerChar GPC-IR (Valencia, Spain) high-temperature GPC chromatograph equipped with an internal IR5 detector. The autosampler oven compartment was set at 160 °C and the column compartment was set at 150 °C. The columns used were three Agilent "Mixed B" 30 cm 10 micron linear mixed-bed columns and a 10 μm precolumn. The chromatography solvent used was 1,2,4-trichlorobenzene, which contained 200 ppm of butylated hydroxytoluene (BHT). The solvent source was sparged with nitrogen. The injection volume used was 200 microliters and the flow rate was 1.0 milliliter / minute.

[0089] Calibration of the GPC column set was performed using 21 narrow molecular weight distribution polystyrene standards with molecular weights in the range of 580 to 8,400,000 g / mol, placed in six "cocktail" mixtures having at least one order of magnitude spacing 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 of 1,000,000 g / mol and above, and 0.05 grams in 50 milliliters of solvent for molecular weights below 1,000,000 g / mol. The polystyrene standards were dissolved at 80 °C for 30 minutes with gentle stirring. The polystyrene standard peak molecular weights were converted to polyethylene molecular weights using Equation 1 (as described in Williams and Ward, J. Sci., Polym. Let., 6, 621 (1968)). M ポリエチレン =A×(M ポリスチレン ) B (EQ1) Where M is the molecular weight, A has a value of 0.4315, and B is equal to 1.0.

[0090] The fifth-degree polynomial was used and applied to each polyethylene equivalent calibration point. A slight adjustment (about 0.415 - 0.44) to A was made to correct for column resolution and band spreading effects so that the NIST standard NBS1475 was obtained at 52,000 g / mol (Mw).

[0091] The total plate count of the GPC column set was performed with eicosane (prepared at 0.04 g in 50 milliliters of trichlorobenzene (TCB) and dissolved for 20 minutes with gentle stirring). The plate count (Equation 2) and symmetry (Equation 3) were measured with a 200 microliter injection according to the following equations.

Number

Number

[0092] Samples were prepared in a semi-automatic fashion using PolymerChar "Instrument Control" software: 2 mg / ml was used as the target weight of the sample, and through the PolymerChar high-temperature autosampler, the solvent (containing 200 ppm of BHT) was added to a vial with a septum cap that had been pre-sparged with nitrogen. The samples were dissolved at 160 degrees Celsius for 2 hours while shaking at "low speed".

[0093] The calculations of Mn, Mw, and Mz were based on GPC results using the internal IR5 detector (measurement channel) of a PolymerChar GPC-IR chromatograph, the PolymerChar GPCOne™ software, the IR chromatogram with the baseline subtracted at each equidistant data collection point (i), and the polyethylene equivalent molecular weight obtained from the narrow standard calibration curve for point (i) from Equation 1.

Number

Number

Number

[0094] To monitor the deviation over time, a flow marker (decane) was introduced into each sample via a micropump controlled by the PolymerChar GPC-IR system. This flow marker was used to linearly calibrate the flow rate of each sample by matching each decane peak in the sample with the decane peak within the narrow standard calibration. Thus, any change in the time of the decane marker peak is presumed to be related to a linear shift in both the flow rate and the chromatography gradient. To facilitate the highest accuracy in the RV measurement of the flow marker peak, a least-squares fitting routine was used to fit the peak of the flow marker concentration chromatogram to a quadratic equation. Next, the first derivative of the quadratic equation was used to determine the true peak position. After calibrating the system based on the flow marker peak, the effective flow rate (as the measured value of the calibration gradient) was calculated as in Equation 7. The processing of the flow marker peak was performed by the PolymerChar GPCOne™ software.

Number

[0095] Improved method for comonomer content distribution (iCCD) analysis The improved comonomer content distribution (iCCD) analysis method was carried out using a Crystallization Elution Fractionation (CEF) instrument (PolymerChar, Spain) equipped with an IR-5 detector (PolymerChar, Spain) and a dual-angle light scattering detector model 2040 (Precision Detectors, now Agilent Technologies). Immediately before the IR-5 detector in the detector oven, a guard column filled with 20 - 27 micron glass (MoSCi Corporation, USA) in 10 cm (length) × 1 / 4 inch (ID) (0.635 cm ID) stainless steel was attached. Orthodichlorobenzene (ODCB, 99% anhydrous grade or technical grade) was used. Silica gel 40 (particle size 0.2 - 0.5 mm, catalog number 10181-3) was obtained from EMD Chemicals (the packed column, which can be used to fill the column and further purify ODCB, is attached after the outlet of the Agilent pump). The CEF instrument was equipped with an autosampler with N2 purge capability. ODCB was sparged with dry nitrogen (N2) for 1 hour before use. Sample preparation was carried out at 160 °C with shaking for 1 hour using the autosampler at 4 mg / mL (unless otherwise specified). The injection volume was 300 μL. The temperature profile for iCCD was crystallization at 105 °C to 30 °C at 3 °C / min, thermal equilibrium at 30 °C for 2 minutes (including the soluble fraction elution time set as 2 minutes), and elution at 30 °C to 140 °C at 3 °C / min. The flow rate during crystallization was 0.0 ml / min. The flow rate during elution was 0.50 ml / min. Data was collected at 1 data point / second.

[0096] The iCCD column was packed with nickel particles (Bright 7GNM8-NiS, Nippon Chemical Industry) coated with gold in a 15 cm (length) × 1 / 4 inch (ID) (0.635 cm) stainless steel tube. Column packing and conditioning were performed using the slurry method according to the reference (Cong, R; Parrott, A.; Hollis, C.; Cheatham, M. US Patent Application Publication No. 2018 / 0172648A1). The final pressure of the TCB slurry packing was 150 bar.

[0097] Column temperature calibration was performed using a mixture of the linear homopolymer polyethylene of the standard substance (comonomer content zero, melt index (I2) 1.0, polydispersity Mw / Mn approximately 2.6 in conventional gel permeation chromatography, having 1.0 mg / mL) and eicosane (2 mg / mL) in ODCB. The iCCD temperature calibration consists of the following four steps. (1) Calculating the delay volume defined as the temperature offset during the subtraction of 30.00 °C from the measured peak elution temperature of eicosane, (2) subtracting the temperature offset of the elution temperature from the iCCD raw temperature data, where it is noted that this temperature offset is a function of experimental conditions such as elution temperature, elution flow rate, etc., (3) creating a linear calibration straight line for converting the elution temperature over the range of 30.00 °C to 140.00 °C such that the linear homopolymer polyethylene standard has a peak temperature of 101.0 °C and eicosane has a peak temperature of 30.0 °C, (4) linearly extrapolating the elution temperature below 30.0 °C for the soluble fraction measured isothermally at 30 °C by using an elution heating rate of 3 °C / min according to the reference (US2018 / 0172648A1).

[0098] The elution temperature versus the comonomer content of the iCCD was constructed using 12 standard substances (ethylene homopolymers and ethylene-octene random copolymers made with single-site metallocene catalysts, having ethylene equivalent average molecular weights in the range of 35,000 to 128,000 g / mol). All of these standard substances were analyzed in the same manner as previously specified at 4 mg / mL. By modeling the reported elution peak temperature as a function of octene mol% using linear regression, an equation 8 (EQ8) with R 2 equal to 0.978 was obtained. The elution peak is the temperature at which the eluting weight fraction is the highest. (Elution temperature in °C)= -6.3515×(Octene mol%) + 101.000 EQ8

[0099] For the entire resin, an integration window is set to integrate all weight fractions at elution temperatures in the range of 23.0 °C to 115 °C (temperature calibration as specified above). The weight percent of the high density fraction (HDF) of the resin is defined by the following equation 9 (EQ9), the soluble fraction (SF) of the resin is defined by the following equation 10 (EQ10), and the copolymer fraction (CF) is defined by the following equation 11 (EQ11). [Number] [Number] CF = (1 - HDF - SF)×100% EQ11

[0100] Ultimate elongation The ultimate elongation was determined according to the Highlight Test Stand commercially available from Highlight Industries. The test was conducted as follows. A film roll (20 inches wide, thickness specified below) was placed on the unwind section of the machine, and the film was unwound through a set of rollers while the second roller maintained a constant rotational speed (corresponding to a film speed of 180 ft / min) and the rotational speed of the first roller was continuously decreased. Thus, the film was subjected to increasing strain and increasing force, and the test was continued until the film reached the ultimate elongation point (the amount of strain at film breakage between the stretching rollers). The amount of force applied was measured by a load cell and calculated using the ratio of the roller rotational speeds to determine the amount of elongation present in the film. Three tests were performed and averaged together to obtain an average ultimate elongation value. During each test, the load required to stretch the film was recorded by the load cell. The elongation forces recorded at 200% elongation in each test are also averaged below.

[0101] Puncture on the pallet Puncture on the pallet was determined using a Lantech stretch wrapper. Each 20-inch-wide film was wound onto a stretch wrapper set at 250% stretch. It was wound around a rectangular pallet (approx. 35×44 inches) at 10 rpm, and instead of moving the film up and down, it was wound around a fixed part of the test pallet. The test varied the dancer bar "F2" setting (which represents the tension maintained in the film between the pallet and the final stretch roller), which could be changed in 0.5 lbf increments from 7 lbf to 18 lbf. When the wrapper reached 250% pre-stretch, the pallet was wound around a 2-inch×2-inch right-angled prism steel protrusion that extended 6 inches from one corner of the pallet (parallel to the short side of the rectangle). The cross-section of the protrusion is beveled with a curvature radius of approximately 4 mm. The probe was smoothed to remove sharp edges so that the curvature radius of the edge was approximately 2 mm. Each trial consisted of winding the pallet completely three times to cover the probe three times and evaluating whether the probe punctured the film. If the film broke during any of the winding, it was considered a failure at that force-to-load setting. Depending on the performance of the film at the load setting (i.e., pass or fail), the force-to-load was adjusted up or down and the test was repeated at the new load setting. The reported load is the maximum load at which 50% of the tests pass (3 successes out of a maximum of 6 trials). The entire process was run three times and the average was reported as the puncture value on the pallet.

[0102] Table 2 below shows the equipment and settings used in this method.

Table 2

[0103] Total haze Total haze was measured according to ASTM D1003.

[0104] Dirt The film dirt drop test measures the energy required to break a plastic film under specific conditions of impact by free-falling dirt. The test results are expressed as the energy in terms of the weight of a projectile falling from a specific height that will cause 50% breakage of the test specimens being tested.

[0105] The dirt impact strength (dirt) is measured according to ASTM D1709, Method A, using a drop height of 26 inches ± 0.4 inches (66 cm ± 1 cm) and a polished aluminum hemispherical head with a diameter of 38.10 ± 0.13 mm.

Examples

[0106] The following examples are provided to illustrate the embodiments described in the present disclosure and are not intended to limit the present disclosure or its appended claims.

[0107] Catalyst preparation procedure The catalyst preparation procedures for Comparative Examples A - C and Examples 1 - 9 of the present invention are listed below.

[0108] Ziegler - Natta catalyst (without zinc) - Comparative Examples A - C To approximately 220 lb of a 0.20 M MgCl2 slurry, 12.86 lb of a (C2H5)AlCl2 (EADC) solution (15 wt% in heptane) was added and subsequently stirred for 8 hours. Next, 6.64 lb of a TiCl4 / VOCl3 mixture (1.10 wt% Ti and 2.36 wt% V in heptane) was added, followed by a solution of Zr(TMHD)4 (zirconium tetrakis(2,2,6,6 - tetramethyl - 3,5 - heptanedionate)) (1.34 wt% Zr solution in 5.19 lb of heptane). These two additions were carried out continuously within 1 hour of each other. The resulting catalyst premix was aged with further stirring for 8 hours before use.

[0109] Ziegler - Natta catalyst (containing zinc) - Examples 1 - 3 and 9 of the present invention To a 0.20 M MgCl2 slurry of about 210 lb, 12.52 lb of a (C2H5)AlCl2 (EADC) solution (15 wt% in heptane) was added, followed by stirring for 4 hours. A solution of Zn(EHA)2 (zinc 2-ethylhexanoate) (5.0 wt% Zn in 3.81 lb of Isopar-E) was added, followed by stirring for 4 hours. Next, 6.34 lb of a TiCl4 / VOCl3 mixture (1.10 wt% Ti and 2.36 wt% V in heptane) was added. The resulting catalyst premix was aged with further stirring for 8 hours before use.

[0110] Ziegler-Natta catalyst (containing zinc) - Examples 4 to 7 of the present invention To a 0.20 M MgCl2 slurry of about 220 lb, 13.12 lb of a (C2H5)AlCl2 (EADC) solution (15 wt% in heptane) was added, followed by stirring for 4 hours. A solution of Zn(EHA)2 (zinc 2-ethylhexanoate) (5.0 wt% Zn in 3.99 lb of Isopar-E) was added, followed by stirring for 4 hours. Next, 6.64 lb of a TiCl4 / VOCl3 mixture (1.10 wt% Ti and 2.36 wt% V in heptane) was added. The resulting catalyst premix was aged with further stirring for 8 hours before use.

[0111] Ziegler-Natta catalyst (containing zinc) - Example 8 of the present invention To a 0.20 M MgCl2 slurry of about 215 lb, 12.82 lb of a (C2H5)AlCl2 (EADC) solution (15 wt% in heptane) was added, followed by stirring for 4 hours. A solution of Zn(EHA)2 (zinc 2-ethylhexanoate) (5.0 wt% Zn in 3.90 lb of Isopar-E) was added, followed by stirring for 4 hours. Next, 6.49 lb of a TiCl4 / VOCl3 mixture (1.10 wt% Ti and 2.36 wt% V in heptane) was added. The resulting catalyst premix was aged with further stirring for 8 hours before use.

[0112] Production of Comparative Examples A to C and Examples 1 to 9 of the present invention Comparative Examples A - C and Examples 1 - 9 of the present invention were produced via solution polymerization by the following exemplary process. Before introducing into the reaction environment, all raw materials (monomers) and process solvents (high - purity isoparaffin solvent with a narrow boiling range, Isopar - E) were purified by molecular sieving. Hydrogen was supplied in a high - purity grade in a pressurized cylinder and was not further purified. The reactor monomer feed stream was pressurized via a mechanical compressor to a pressure exceeding the reaction pressure. The solvent supply was pressurized via a pump to a pressure higher than the reaction pressure. Each individual catalyst component was manually batch - diluted with the purified solvent to a specific component concentration and pressurized to a pressure higher than the reaction pressure. All reaction feed streams were measured with mass flow meters and independently controlled by a computer - automated valve control system.

[0113] The continuous solution polymerization reactor was a liquid - filled non - adiabatic isothermal circulation loop reactor similar to a continuous stirred - tank reactor (CSTR) with heat removal. Independent control of all unused solvent, monomer, hydrogen, and catalyst component feeds was possible. The fresh feed streams (solvent, monomer, and hydrogen) to the reactor were temperature - controlled by passing the feed streams through a heat exchanger. The catalyst components were injected into the polymerization reactor through specially designed injection needles and combined into one mixed catalyst / cocatalyst feed stream before injection into the reactor. The supply of the primary catalyst component was computer - controlled to maintain the reactor monomer concentration at a specific target. The cocatalyst component was supplied to the primary catalyst component based on a calculated specific molar ratio. Immediately after each fresh injection location (either feed or catalyst), the feed stream was mixed with the contents of the circulating polymerization reactor using a static mixing element. The contents of the reactor were continuously circulated through a heat exchanger that served to remove most of the reaction heat and at the coolant - side temperature that served to maintain an isothermal reaction environment at a specific temperature. The circulation around the reactor loop was performed by a positive - displacement pump.

[0114] The final reactor effluent entered the zone where it was deactivated by the addition of water and reaction with water. At this same reactor outlet location, other additives were added (e.g., acid scavengers and antioxidants). Next, the stream passed through a static mixer to disperse the post-reactor additive components.

[0115] Following catalyst deactivation and additive addition, the reactor effluent entered a devolatilization system where the polymer was removed from the non-polymer stream. The isolated polymer melt was pelletized and collected. The non-polymer stream passed through various equipment that separated most of the ethylene removed from the system. Most of the solvent and unreacted monomer were passed through a purification system and then recycled back to the reactor. A small amount of solvent and monomer was purged from the process.

[0116] Tables 3A and 3B summarize the polymerization conditions for the syntheses of Comparative Examples A - C and Examples 1 - 9 of the present invention, respectively. The additives used in these polymerizations were 1000 ppm of IRGAFOS™ 168 (which is tris(2,4-di-tert-butylphenyl) phosphite), 250 ppm of IRGANOX™ 1076 (which is octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate), and 200 ppm of IRGANOX™ 1010 (tetrakis(methylene(3,5-di-tert-butyl-4-hydroxyhydrocinnamate)) methane). IRGAFOS™ 168 and IRGANOX™ 1076 are commercially available from BASF. IRGANOX™ 1010 is available from BASF. All of these examples were produced in a single reactor using 1-hexene as a comonomer.

Table 3

Table 4

[0117] Examples of Inflation Films Table 4 includes the properties of the resins used in the following examples of inflation films. As shown, Table 4 includes the properties of the resin examples of Tables 3A and 3B, as well as the properties of other conventional resins (Comparative Examples D - G) listed below, all of which are available from Dow Inc., Midland, MI.

Table 5-1

Table 5-2

[0118] A single-layer inflation film containing 100 wt% LLDPE was produced using a polyethylene "Davis Standard Barrier II screw" with an "8-inch die" (single-screw extruder). External cooling by an air ring and internal bubble cooling were used. The film thickness was controlled within ±10% at 2 mils by adjusting the nip roller speed. The bubble layflat was 31 inches wide. The film was wound onto a roll. The general inflation film parameters used for the production of each inflation film are shown in Table 5A. The temperatures are those closest to the pellet hopper (barrel 1) and ascending as the polymer is extruded through the die.

[0119] The inflation films listed in Tables 5B and 5C below utilized the parameters presented in the same table.

Table 6

Table 7

Table 8

[0120] Referring to Tables 5A and 5B above, the inflation film IBF2 of the present invention exhibits far superior (higher) dirt and improved (lower) haze compared to the comparative inflation film CBF1 having similar density and melt index. Without being bound by theory, this improved balance of dirt and total haze performance is thought to be partially due to the short-chain branch distribution defined by the soluble fraction, copolymer fraction, and high-density fraction of the iCCD.

[0121] The improvement in dirt and haze is also shown in comparison with conventional inflation films CBF4 - CBF7. For example, when comparing the inflation film IBF4 of the present invention and the comparative inflation film CBF7, both having similar density and melt index, IBF4 exhibited better total haze and dirt performance. Similarly, when comparing IBF5 and CBF4, both having similar density and melt index, IBF5 exhibited better haze and dirt performance. When comparing IBF7 and CBF6, both having the same density, IBF7 exhibited better total haze and dirt performance.

[0122] Cast film Table 6 below presents resins and resin properties for resins incorporated into or suitable for use in cast films. As shown in Table 6, Comparative Example H(CH) is DOWLEX™ GM 8480F available from The Dow Chemical Company, Midland, MI. Comparative Example I(CI) is ELITE 5230G, also available from The Dow Chemical Company, Midland, MI. The cast film of the present invention includes Example Resin 8 of the present invention (IE8). However, Example Resin 9 of the present invention (IE9) is another resin suitable for use in cast films. The polymerization conditions for IE8 and IE9 are presented in Table 3B.

Table 9

[0123] Production of the Stretched Cast Film Using the resins listed in Table 6 above, a 5-layer (A / B / C / D / E) film was produced as follows on a 5-layer Egan-Davis standard cast extrusion line. The die gap was 20 mils, the melt curtain used was 3.5 inches, the cast roll was maintained at 70°F, the die was maintained at 550°F, and the line speed was operated to reach the target film thickness. One extruder (A) provided ATTANE 4404 to form one surface layer (adhesive layer), and the remaining extruders provided IE8, CH, or CI. The inventive cast films (ICF1 and ICF2) used IE8, the comparative cast films CCF1 and CCF2 used CH resin, and CCF3 used CI. ATTANE 4404G is a polyethylene resin commercially available from The Dow Chemical Company, with an I2 of 4.0 g / 10 min and a density of 0.904 g / cc. The target layer structure was as follows (weight %): 10 / 23 / 30 / 26 / 11. The A layer (adhesive layer) faced the core of the roll during the winding process. Table 7 below shows the target film thickness, throughput, extruder temperature, and line speed. [Table 10]

[0124] After production of the cast films in Table 7, the cast films were evaluated based on extreme stretching, Highlight (200%) stretching force, and puncture on the pallet. The results of these tests are shown in Table 8. [Table 11]

[0125] As shown above, the cast films ICF1 and ICF2 of the present invention showed the best combination of Highlight ultimate elongation, Highlight 200% elongation force, and puncture on the pallet. Comparing ICF1 with CCF1 having the same 0.5 mil thickness, it is clear that ICF1 has excellent ultimate elongation, Highlight elongation force, and puncture on the pallet. Similarly, comparing ICF1 with CCF3 having the same thickness, the puncture and ultimate elongation may be equivalent. However, ICF1 has significantly better Highlight elongation force performance. Similarly, comparing ICF2 of 0.7 mil film with CCF2, ICF2 shows a combination of improved puncture and Highlight elongation force, and equal ultimate elongation. Without being bound by theory, these improvements are considered to be due to changes in the polymer structure described by the soluble fraction, copolymer fraction, high-density fraction, and the ratio of soluble fraction to high-density fraction in Table 6.

[0126] Higher ultimate elongation is beneficial as it enables wrapping pallets under a wider range of conditions and minimizes film breakage during the winding process. A higher load at a specific elongation (measured in the Highlight 200% elongation force test) indicates a harder film, which correlates with excellent fracture resistance during pallet transportation. A higher puncture value on the pallet is beneficial, indicating higher overall film abuse resistance. It should be noted that the present invention includes the following aspects. [Aspect 1] A linear low-density polyethylene (LLDPE) polymer, wherein the LLDPE is a polymerization reaction product of an ethylene monomer and a C 3 -C 12 ethylene comonomer, the LLDPE has a density of 0.904 to 0.925 g / cc and a melt index (I) of 0.5 to 1.5 g / 10 min when measured according to ASTM 1238 under a load of 2.16 kg at a temperature of 190 °C. 2 ) 、 I 10 The melt flow ratio (I) is 6.5 to 7.6 as measured according to ASTM 1238 at a temperature of 190 °C under a load of 10 kg, 10 / I 2 and has a molecular weight distribution (MWD = Mw / Mn) of 2.5 to 3.6 when measured by gel permeation chromatography, the LLDPE is a copolymer fraction of more than 85%, defined as the ratio of the mass eluted at a temperature above 35 °C to less than 95 °C to the total eluted mass when measured using an improved comonomer content distribution (iCCD) curve of elution mass versus temperature, a copolymer fraction, a high-density fraction of 0.5 to 8.0%, defined as the ratio of the mass eluted at a temperature of 95 °C or higher to the total mass, a high-density fraction, a soluble fraction of 1.0% to 12.0%, defined as the ratio of the mass eluted at a temperature of 35 °C or lower to the total mass, a soluble fraction and includes a short-chain branch distribution defined by the above, an LLDPE polymer. [Aspect 2] An inflation film containing the LLDPE described in Aspect 1. [Aspect 3] The inflation film according to Aspect 2, having a dirt value of at least 900 g and a resin density of less than 0.918 g / cc when the thickness of the inflation film is 2.0 mils. [Aspect 4] The inflation film according to Aspect 2 or 3, having a total haze (%) of 4.5% to 10.5% when the thickness of the inflation film is 2.0 mils. [Aspect 5] The I 2 is less than 1.5, and the inflation film according to any one of Aspects 2 to 4. [Aspect 6] The inflation film according to any one of Aspects 2 to 5, having a thickness of 0.5 to 6 mils. [Aspect 7] The inflation film according to any one of Aspects 2 to 6, wherein the soluble fraction is less than 5%. [Aspect 8] The inflation film according to any one of Aspects 2 to 7, wherein the copolymer fraction exceeds 90%. [Aspect 9] The inflation film according to any one of Aspects 2 to 8, further comprising LDPE. [Aspect 10] The inflation film according to Aspect 9, wherein the inflation film comprises 50 to 95% by weight of the LLDPE and 5 to 50% by weight of the LDPE. [Aspect 11] The inflation film according to any one of Aspects 2 to 10, wherein the inflation film is a multilayer film. [Aspect 12] A linear low density polyethylene (LLDPE) polymer, wherein the LLDPE comprises a polymerization reaction product of an ethylene monomer and a C 3 -C 12 ethylene comonomer, the LLDPE has a density of about 0.910 to 0.920 g / cc, a melt index (I 2 ) of 2.0 to 7.0 g / 10 minutes when measured according to ASTM 1238 under a load of 2.16 kg at a temperature of 190 ° C, and 10 I 10 / I 2 has a melt flow ratio (I ) of 6.5 to 7.6 measured according to ASTM 1238 at a temperature of 190 ° C under a load of 10 kg, the LLDPE has a high density fraction of 0.5 to 6.0%, defined as the ratio of the mass eluted in the temperature range of 95 ° C or higher to the total eluted mass when measured using an iCCD curve of eluted mass versus temperature, a high density fraction, a soluble fraction of 1.0 to 3.0%, defined as the ratio of the mass eluted in the temperature range of 35 ° C or lower to the total eluted mass, a soluble fraction, the ratio of the soluble fraction to the high density fraction is 0.40 to 0.65, and the maximum elution peak height occurs at a temperature exceeding 80 ° C and includes a short chain branch distribution defined by. [Aspect 13] The LLDPE according to Aspect 12, wherein the high density fraction is 3.0% to 6.0%. [Aspect 14] The LLDPE according to Aspect 12 or 13, wherein the soluble fraction is 2.0% to 3.0%. [Aspect 15] The LLDPE according to any one of Aspects 12 to 14, wherein the LLDPE has a copolymer fraction of more than 85%, and the copolymer fraction is defined as the ratio of the mass eluted at a temperature of 35 ° C to 95 ° C to the total mass when measured using an iCCD curve of eluted mass versus temperature. [Aspect 16] The LLDPE according to any one of Aspects 12 to 15, wherein the maximum elution peak height occurs at a temperature of less than 90 ° C. [Aspect 17] A cast film comprising the LLDPE according to any one of Aspects 12 to 16. [Aspect 18] The cast film according to embodiment 17, further comprising LDPE. [Embodiment 19] The cast film according to embodiment 17, wherein the cast film comprises 50 to 95% by weight of the LLDPE and 5 to 50% by weight of the LDPE. [Embodiment 20] The cast film according to any one of embodiments 17 to 19, wherein the cast film is a multilayer film.

Claims

1. A linear low density polyethylene (LLDPE) polymer, The said LLDPE polymer is a polymerization reaction product of ethylene monomer and C ３ -C １２ ethylene comonomer, and The LLDPE polymer has a density of 0.904 to 0.925 g / cc, a melt index (I ２ ), when measured according to ASTM 1238 under a load of 2.16 kg at a temperature of 190 °C, of 0.5 to 1.5 g / 10 min, a melt flow ratio (I １０ / I ２ ), where I １０ is measured according to ASTM 1238 at a temperature of 190 °C under a load of 10 kg, and has a molecular weight distribution (MWD = Mw / Mn) of 2.5 to 3.6 when measured by gel permeation chromatography, wherein the LLDPE polymer is a copolymer fraction exceeding 85%, defined as the ratio of the mass eluted at a temperature above 35°C and below 95°C to the total eluted mass when measured using an improved comonomer content distribution (iCCD) curve of elution mass versus temperature, where the iCCD curve is obtained according to the iCCD analysis method described herein, a high density fraction of 0.5 to 8.0%, defined as the ratio of the mass eluted at a temperature of 95°C or higher to the total mass, a soluble fraction of 1.0% to 12.0%, defined as the ratio of the mass eluted at a temperature of 35°C or lower to the total mass and contains a short chain branch distribution defined thereby, the LLDPE polymer.

2. An inflation film comprising the LLDPE polymer according to Claim 1.

3. The inflation film according to Claim 2, having at least 900 g of dirt value and a resin density of less than 0.918 g / cc when the thickness of the inflation film is 0.0508 mm (2.0 mil).

4. The inflation film according to Claim 2 or 3, having a total haze (%) of 4.5% to 10.5% when the thickness of the inflation film is 0.0508 mm (2.0 mil).

5. Said I ２ The inflation film according to any one of claims 2 to 4, wherein is less than 1.

5.

6. The inflation film according to any one of Claims 2 to 5, having a thickness of 0.0127 to 0.1524 mm (0.5 to 6 mil).

7. The inflation film according to any one of Claims 2 to 6, wherein the soluble fraction is less than 5%.

8. The inflation film according to any one of Claims 2 to 7, wherein the copolymer fraction exceeds 90%.

9. The inflation film according to any one of Claims 2 to 8, further comprising LDPE.

10. The inflation film according to Claim 9, wherein the inflation film comprises 50 to 95% by weight of the LLDPE polymer and 5 to 50% by weight of the LDPE.

11. The inflation film according to any one of Claims 2 to 10, wherein the inflation film is a multilayer film.

12. A linear low-density polyethylene (LLDPE) polymer, wherein the LLDPE polymer comprises a polymerization reaction product of an ethylene monomer and a C ３ -C １２ ethylene comonomer, The LLDPE polymer has a density of 0.910 to 0.920 g / cc and a melt index (I ２ ) of 2.0 to 7.0 g / 10 min when measured according to ASTM 1238 under a load of 2.16 kg at a temperature of 190 °C, and a melt flow ratio (I １０ / I ２ ) of 6.5 to 7.6, where I １０ is measured according to ASTM 1238 at a temperature of 190 °C under a load of 10 kg, The LLDPE polymer A high-density fraction of 0.5 to 6.0%, defined as the ratio of the mass eluted within a temperature range of 95 °C or higher to the total eluted mass when measured using an improved comonomer content distribution (iCCD) curve of elution mass versus temperature, where the iCCD curve is obtained according to the iCCD analysis method described herein, A soluble fraction of 1.0 to 3.0%, defined as the ratio of the mass eluted within a temperature range of 35 °C or lower to the total eluted mass, The ratio of the soluble fraction to the high-density fraction is 0.40 to 0.65, The maximum elution peak height occurs at a temperature exceeding 80 °C An LLDPE polymer containing a short-chain branch distribution defined by the above.

13. The LLDPE polymer according to claim 12, wherein the high-density fraction is 3.0% to 6.0%.

14. The LLDPE polymer according to claim 12 or 13, wherein the soluble fraction is 2.0% to 3.0%.

15. The LLDPE polymer according to any one of claims 12 to 14, wherein the LLDPE polymer has a copolymer fraction exceeding 85%, and the copolymer fraction is defined as the ratio of the mass eluted at a temperature of 35 °C to 95 °C to the total mass when measured using an iCCD curve of elution mass versus temperature.

16. The LLDPE polymer according to any one of claims 12 to 15, wherein the maximum elution peak height occurs at a temperature below 90 °C.

17. A cast film comprising the LLDPE polymer according to any one of claims 12 to 16.

18. The cast film according to claim 17, further comprising LDPE.

19. The cast film according to claim 17, wherein the cast film comprises 50 to 95% by weight of the LLDPE polymer and 5 to 50% by weight of the LDPE.

20. The cast film according to any one of claims 17 to 19, wherein the cast film is a multilayer film.

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