Modified polyethylene and articles made therefrom

Abstract

The present disclosure provides modified polyethylene, articles (e.g., films) made therefrom, and methods of forming the compositions and films. Films from blends of certain polyethylenes and certain modifiers exhibit a new and useful balance of properties. By adding modifiers, the maximum throughput of film production equipment can be increased while maintaining or improving other film properties of polyethylene, such as stiffness, tear resistance, tensile strength and sealing properties. Surprisingly, the optical properties (e.g., haze) of the polyethylene film are significantly improved by the addition of a modifier.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 482,883, filed February 2, 2023, entitled “Modified Polyethylene and Articles Made Therefrom,” the entire contents of which are incorporated herein by reference. Technical Field

[0002] The present disclosure provides modified polyethylenes, articles made therefrom (eg, films), and methods of forming the compositions and films. Background Art

[0003] Polyethylene and the composition containing polyethylene can be used for many applications, for example, for film.For example, blown film technology is a useful way to make polyethylene film.A kind of purposes of this film is to make bags, wherein film can be formed into a continuous cylinder, then curled to close one end.However, the method that polyethylene is blown into this type of film relates to the balance between the processability (for example, fluidity and melt strength) of polymer on the one hand and the mechanical properties (for example, tensile strength, modulus) of polymer on the other hand.Improving processability while maintaining mechanical properties can be conducive to the production rate that improves and produces film and bag more economically.

[0004] Polyethylene polymers are typically made from ethylene and C3-C6 olefin comonomers with various catalyst systems using Ziegler-Natta catalysts, chromium catalysts, metallocene catalysts, etc., in a variety of processes including gas phase processes, solution processes, high pressure tubular processes, slurry processes, and sometimes combinations of these processes.

[0005] Typically, metallocene-catalyzed polyethylene (mPE) may be more difficult to process than low-density polyethylene (LDPE) prepared in a high-pressure polymerization process. For example, mPE (which often has a narrow molecular weight distribution and a low level of branching) requires more motor power and produces a higher extruder pressure to match the extrusion rate of LDPE. Typical mPE also has a lower melt strength, which, for example, reduces bubble stability during blown film extrusion and reduces melt fracture stability under commercial shear rates. On the other hand, compared to LDPE, mPE exhibits excellent physical properties for some applications. Various levels of LDPE can be blended with mPE to increase melt strength, increase shear sensitivity, for example, increase flow under commercial shear rates in an extruder; and reduce melt fracture. However, these blends typically have mechanical properties that are poorer than pure mPE.

[0006] As for bubble stability, high melt strength is desirable for blown film processability because it provides bubble stability. In polyethylene, molecular weight, molecular weight distribution and long chain branching have an impact on melt strength. Reducing melt index and widening molecular weight distribution on the high molecular weight side can effectively achieve high melt strength, but inevitably increase melt viscosity and therefore reduce extrudability. Strengthening melt strength by long chain branching (LCB) (by directly introducing LCB into the polyethylene backbone or LDPE being blended into the base resin) has a negative impact on the mechanical properties of the film. It would be advantageous to be able to control the melt strength of the polymer composition without hindering melt extrusion and physical properties.

[0007] Increased melt strength is a desirable property for many polyolefin applications, including films and fibers. Higher melt strength allows manufacturers to run their blown film lines at faster rates. It also allows them to process thicker films in applications such as geoprocessing films.

[0008] References of potential interest in this regard include: US2007 / 0260016; US 5,670,595; US 6,903,162; US 6,509,431; US10,808,049; US 10,125,247; US2020 / 0223951 and US2018 / 0265657.

[0009] There is still a need for modified polyethylene and films having, for example, high melt strength and maintained or improved melt extrudability and other physical properties. There is also a need for methods of forming modified polyethylene and films having, for example, high melt strength and maintained or improved melt extrudability and other physical properties. Summary of the Invention SUMMARY OF THE INVENTION

[0010] In one aspect, embodiments of the present invention provide a modified polyethylene composition comprising the product of a combination of: (1) 90-99.9 wt% of a polyethylene glycol comprising 85-99.9 wt% of units derived from ethylene and units derived from C3 to C 10 A polyethylene containing α-olefin units, the polyethylene having a molecular weight of 0.900 to 0.940 g / cm 3 and (2) 0.10-10 wt% of an ethylene copolymer elastomer modifier, said modifier comprising at least 70 wt% of units derived from ethylene and 0.01-20 wt% of units derived from C3 to C 10 In some embodiments, the modifier may further comprise 0.01-10 wt. % of units derived from a cyclic-diene monomer, such that the modifier is a cyclic-diene ethylene terpolymer. Whether a copolymer or, more specifically, a terpolymer, the modifier is preferably highly branched.

[0011] Other embodiments of the present invention provide improved films formed from such modified polyethylene compositions and improved methods of producing films from such modified polyethylenes.

[0012] The present inventors have discovered that films from blends of certain polyethylenes and certain modifiers exhibit a novel and useful balance of properties. Furthermore, the maximum output of film production equipment can be increased by as much as 15% or more, while maintaining or improving other film properties of the polyethylene, such as stiffness, tear resistance, tensile strength, and sealability, where the modifier is added to the polyethylene at 10% or less of the total composition. Surprisingly, optical properties of the polyethylene film, such as haze, are significantly improved by the addition of 10% or less of the modifier to the total composition. Detailed Description of the Invention

[0013] The present disclosure provides modified polyethylene compositions, films comprising such compositions, and methods for preparing films comprising such compositions. Films from the modified polyethylene of the present disclosure and / or formed by the methods of the present disclosure exhibit new and useful property combinations. Achieve high melt strength while maintaining or improving melt viscosity (i.e., shear thinning in the processing of the modified polyethylene); all of which simultaneously have minimal impact (if any) on film physical properties. Stiffness, tear resistance, tensile strength, and sealing properties are typically maintained or enhanced by adding 10% or less of a modifier to the polyethylene, based on the total composition. Although dart impact performance is slightly reduced when a modifier is added to polyethylene, this can far exceed the previously mentioned film properties providing the same or improved performance at increased production rates. In addition, by adding a modifier, such as 10% by weight or less of the total modified polyethylene composition, preferably 5% by weight or less (based on the mass of the modified polyethylene composition), the optical properties of the polyethylene, such as haze, are significantly improved.

[0014] These properties provide improvements in bubble stability and provide a significant increase in film production compared to conventional compositions and methods. Increased melt strength (e.g., extensional strain hardening) allows the bubble to balance its own weight before solidifying, thereby contributing to improved bubble stability, film thickness uniformity, and the ability to blow large bubbles (e.g., geomembranes). definition

[0015] For purposes of this disclosure, the numbering scheme for the Periodic Table Groups is according to the new notation of the IUPAC Periodic Table of the Elements.

[0016] As used herein, "olefin polymerization catalyst(s)" refers to any catalyst capable of coordination polyaddition, typically, an organometallic complex or compound, in which successive monomers are added into the monomer chain at an organometallic active center.

[0017] The terms "substituent," "radical," "group," and "moiety" are used interchangeably.

[0018] When used herein and unless otherwise specified, the term “C n ” refers to hydrocarbon(s) containing n carbon atoms(s) per molecule, where n is a positive integer.

[0019] As used herein and unless otherwise specified, the term "hydrocarbon" refers to a class of compounds containing hydrogen bonded to carbon, and encompasses (i) saturated hydrocarbon compounds, (ii) unsaturated hydrocarbon compounds, and (iii) mixtures of hydrocarbon compounds (saturated and / or unsaturated), including mixtures of hydrocarbon compounds having different values ​​of n.

[0020] "Olefins," or "olefins," are linear, branched, or cyclic compounds of carbon and hydrogen having at least one double bond. For purposes of this specification and the appended claims, when a polymer or copolymer is referred to as containing an olefin, the olefin present in such polymer or copolymer is the polymerized form of the olefin. For example, when a copolymer is said to have an "ethylene" content of 35% to 55% by weight, it is understood that the monomer units in the copolymer are derived from ethylene in the polymerization reaction, and that the derived units are present at 35% to 55% by weight, based on the weight of the copolymer.

[0021] A "polymer" has two or more monomeric ("mer") units that are the same or different. A "homopolymer" is a polymer containing identical monomeric units. A "copolymer" is a polymer having two or more monomeric units that are different or distinct from each other. A "terpolymer" is a polymer having three or more monomeric units that are different or distinct from each other. "Different" or "different" as used in reference to monomeric units means that the monomeric units differ from each other by at least one atom or are isomerically different. Thus, the definition of copolymer as used herein includes terpolymers and the like. An "ethylene polymer" or "ethylene copolymer" is a polymer or copolymer comprising at least 50% by weight ethylene-derived units, a "propylene polymer" or "propylene copolymer" is a polymer or copolymer comprising at least 50% by weight propylene-derived units, and so forth.

[0022] "Polymerizable conditions" refers to those conditions, including temperature, pressure, reactant concentrations, optional solvent / diluent, reactant mixing / addition parameters, and other conditions selected by the skilled artisan to facilitate the reaction of one or more olefin monomers when contacted with an activated olefin polymerization catalyst to produce the desired polyolefin polymer, typically via coordination polymerization, within at least one polymerization reactor.

[0023] The term "continuous" refers to a system that operates without interruption or stopping. For example, a continuous process for making a polymer would be one in which the reactants are continuously introduced into one or more reactors and the polymer product is continuously withdrawn.

[0024] A "catalyst composition" or "catalyst system" is a combination of at least two catalyst compounds, a support material, an optional activator, and an optional co-activator. For purposes of this invention and the claims thereto, when a catalyst system or composition is described as comprising neutral, stable forms of the components, it will be understood by those skilled in the art that the ionic form of the components is the form that reacts with the monomer to produce the polymer. When used to describe the form after activation, it refers to the support, activation complex, and activator or other charge-balancing moieties. The transition metal compound can be neutral, as in a procatalyst, or a charged species with a counterion, as in an activated catalyst system.

[0025] Coordination polymerization is an addition polymerization in which successive monomers are added into or onto an organometallic active center to produce and / or grow a polymer chain.

[0026] The terms "cocatalyst" and "activator" are used interchangeably herein and are defined as any compound capable of activating any of the catalyst compounds herein by converting the neutral catalyst compound into a catalytically active catalyst compound cation.

[0027] The terms "contact product" or "product of a combination of the following substances" are used herein to describe a composition in which the components are contacted together in any order, in any manner, and for any length of time. For example, the components can be contacted by blending or mixing. In addition, contacting of any component can be carried out in the presence or absence of any other suitable component of the composition described herein. The combination of additional materials or components can be carried out by any suitable method. In addition, the term "contact product" includes mixtures, blends, solutions, slurries, reaction products, etc., or combinations thereof. Although "contact product" can include reaction products, it is not required that the corresponding components react with each other or react in the manner inferred. Likewise, the term "contacted" is used herein to refer to materials that can be blended, mixed, slurried, dissolved, reacted, treated, or otherwise contacted in some other manner.

[0028] A "composition" of the present disclosure may include components of the composition, contact products of the composition, and / or reaction product(s) of components of the composition. A film of the present disclosure may comprise a composition.

[0029] As used herein, "copolymer" refers to a polymer derived from the polymerization of two or more comonomer units, and may, for example, include terpolymers (ie, polymers formed from the polymerization of three comonomer units). polyethylene

[0030] Typically, the polyethylene component of the modified polyethylene composition comprises 85-99.9 wt% of units derived from ethylene, with the remaining balance being units derived from C3 to C 20 , preferably C3 to C 10 Units of α-olefins such as 1-butene, 1-hexene, and / or 1-octene (the weight % being based on the total molecular weight of the polyethylene component). In various embodiments, the polyethylene component may comprise ethylene-derived units in an amount from a lower limit of any of 85, 86, 87, 89, or 91 weight % to an upper limit of 95, 96, 97, 98, 98.5, 99, or 99.5 weight %; wherein ranges from any of the foregoing lower limits to any of the foregoing upper limits are contemplated. In each case, the balance is made up of α-olefin comonomer(s).

[0031] The density of the polyethylene component can be between 0.900 and 0.950 g / cm 3 In the range of, for example, from 0.905, 0.910, 0.911 or 0.912 g / cm 3 The lower limit of any one of 0.915, 0.920, 0.925, 0.930, 0.935, 0.940, 0.945 or 0.950 g / cm 3 any of the upper limits, considering any of the foregoing lower limits to any of the foregoing upper limits (e.g., 0.905 to 0.935 g / cm 3 , or 0.910 to 0.950 g / cm 3 ).

[0032] The melt index (MI, also known as I2 or I 2.16, considering the 2.16 kg load used in the test) can be in the range of 0.1 to 10 g / 10 min (ASTM D1238, 190°C, 2.16 kg load), preferably 0.1 to 5.0 g / 10 min, for example, in the range of any of 0.1, 0.5, 0.7 or 1.0 to an upper limit of any of 1.0, 1.3, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.5 or 10 g / 10 min, with ranges from any of the foregoing lower limits to any of the foregoing upper limits being contemplated (as long as the upper limit is greater than the lower limit).

[0033] In addition, the polyethylene can have a weight average molecular weight (Mw) in the range of 50,000 to 300,000 g / mol, for example, from a lower limit of any of 50,000; 60,000; or 70,000 g / mol to an upper limit of any of 110,000; 115,000; 125,000; 130,000; 140,000; 150,000; 160,000; 165,000; 170,000; 200,000; 250,000; or 300,000 g / mol, wherein ranges from any of the foregoing lower limits to any of the foregoing upper limits are also contemplated herein (e.g., in some embodiments, 50,000 to 120,000 g / mol, or 70,000 to 160,000 g / mol, for example, 70,000 to 130,000 g / mol).

[0034] Specific examples of suitable polyethylenes include various specific types of LLDPE (linear low density polyethylene), and in particular various types of metallocene-catalyzed LLDPE (mLLDPE), such as: (i) narrow composition distribution mLLDPE (referred to herein as narrow-CD mLLDPE); (ii) long chain branched mLLDPE (LCB mLLDPE); (iii) mLLDPE having a combination of narrow molecular weight distribution and broad orthogonal composition distribution (referred to herein as narrow-MWDBOCD-mLLDPE); and (iv) mLLDPE having a combination of broad MWD and BOCD (referred to herein as broad-BOCD-mLLDPE). Each specific example is discussed below in turn. Narrow-CD mLLDPE

[0035] Narrow-CD mLLDPE may, for example, comprise a flat composition distribution metallocene-catalyzed LLDPE (mLLDPE) of 80 to 99.9 wt% ethylene-derived units with the balance being derived from one or more C3 to C 12 Copolymers of units of an alpha-olefin comonomer (and in particular one or more of butene, hexene, octene, preferably one of those, and more preferably hexene). The weight % is based on the total mass of the ethylene-derived units plus the comonomer-derived units in the polyethylene. Such polyethylenes are referred to as having a "flat composition distribution" because the comonomer is incorporated in relatively equal amounts (by weight %) in shorter vs. longer molecular weight chains within the polymer. These may also be referred to as "narrow-CD" or "narrow composition distribution" polyethylenes; or equivalently, high-CDBI mLLDPEs. Composition distribution refers to the distribution of the comonomer in polymer chains of different lengths (different molecular weights), and CDBI refers to Composition Distribution Breadth Index, which is defined as the weight percentage of copolymer molecules (chains) having a comonomer content within 50% of the median total molar comonomer content, and is described in U.S. Patent No. 5,382,630, which is incorporated herein by reference. The CDBI of a copolymer is readily determined using well-known techniques for isolating individual fractions of a copolymer sample. One such technique is temperature rising elution fractionation (TREF), as described in Wild et al., J. Poly. Sci., Poly. Phys. Ed., vol. 20, p. 441 (1982) and U.S. Pat. No. 5,008,204, which are incorporated herein by reference. Thus, a higher value of CDBI indicates a narrow composition distribution (meaning that the comonomer is relatively evenly distributed on polymer chains of different molecular weights).

[0036] Narrow-CD polyethylenes can be prepared using unbridged biscyclopentadienyl Group 4 and substituted forms thereof.

[0037] The narrow-CD polyethylene may have a CDBI of at least 50%, more preferably at least 60%, such as between 50 and 90% or between 60 and 80%.

[0038] The narrow-CD polyethylene may more particularly have an ethylene-derived content in the range of from a lower limit of any of 80, 85, 86, 87, 87.5, 88, 90, 91, 92, 93, 94, or 95 weight percent to an upper limit of any of 88, 90, 93, 94, 95, 96, 97, 98, 99, or 99.9 weight percent; from any of the foregoing lower limits to any of the foregoing upper limits being contemplated, provided that the upper limit is greater than the lower limit (e.g., 85 to 95 weight percent, such as 86 to 92 weight percent ethylene-derived units; or 94 to 99 weight percent ethylene-derived units). The balance is comprised of C3 to C 12The polymer is composed of units derived from an α-olefin comonomer (e.g., hexene).

[0039] The narrow-CD mLLDPE preferably also has one or more, preferably all, of the following additional properties: Vicat softening temperature (ASTM D1525) is within the range of a softening point from 70°C to 130°C, preferably 90°C to 110°C, for example, from a lower limit of any one of 70, 75, 80, 85, 90, 95, 96, 97, 98, 99, or 100°C to an upper limit of any one of 100, 101, 102, 103, 104, 105, 110, 115, 120, 125, or 130°C (ranges from any of the foregoing lower limits to any of the foregoing upper limits are contemplated, provided that the upper limit is greater than the lower limit, for example, 90°C to 110°C or 97°C to 103°C). Melt index (MI, also known as I2 or I 2.16 , considering the 2.16 kg load used in the test) in the range of 0.1 to 5.0 g / 10 min (ASTM D1238, 190°C, 2.16 kg load), for example, from a lower limit of any one of 0.1, 0.2, 0.3, 0.4, 0.5, 0.7 or 0.8 g / 10 min to an upper limit of any one of 1.0, 1.1, 1.2, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5 or 5.0 g / 10 min; ranges from any of the foregoing lower limits to any of the foregoing upper limits are also contemplated. Long chain branching index (LCB index, also referred to herein as g' vis or g' index) is greater than 0.95, preferably greater than or equal to 0.96 or 0.97.

[0040] Narrow-CD mLLDPE may also have one or more, preferably all, of the following: a weight average molecular weight (Mw) in the range of 45,000 to 120,000 g / mol, e.g., 50,000 to 115,000 g / mol or 60,000 to 110,000 g / mol (ranges from any of the foregoing lower limits to any of the foregoing upper limits, e.g., 45,000 to 110,000 g / mol are also contemplated); a number average molecular weight (Mn) in the range of 20,000 to 55,000 g / mol, for example, in the range of 25,000; 30,000; 35,000; or 40,000 to an upper limit of 30,000; 35,000; 40,000; 45,000; 50,000; or 55,000 g / mol, with ranges from any of the foregoing lower limits to any of the foregoing upper limits also contemplated (provided that the upper limit is greater than the lower limit), for example, 35,000 to 55,000 g / mol; a molecular weight distribution (MWD, defined as Mw / Mn) in the range of 1.5 or 2.0 to 3.5 or 4; and Density (ASTM D1505) 0.905 to 0.940 g / cm 3 in the range of, for example, 0.905, 0.910, 0.911, 0.912 or 0.915 g / cm 3 The lower limit of any one of 0.913, 0.914, 0.915, 0.920, 0.925, 0.926, 0.928, 0.930, 0.935 or 0.940 g / cm 3 The range of any upper limit of any of the above, wherein the range from any of the above lower limits to any of the above upper limits is considered (provided that the upper limit is greater than the lower limit), for example, 0.910 to 0.915 g / cm 3 . LCB-mLLDPE

[0041] In some embodiments, mLLDPE can be prepared using a metallocene catalyst that is a bridged biscyclopentadienyl Group 4 and substituted forms thereof, as disclosed in one or more of U.S. Patent Nos. 6,255,426 and 6,476,171, the contents of which are incorporated herein by reference in their entireties. Such catalysts produce polyethylene grades with some long chain branching (compared to the highly linear structure of most mLLDPE) and are referred to herein as "LCB-mLLDPE."

[0042] Compared to other linear low density polyethylenes, in particular compared to other metallocene LLDPEs, long chain branched mLLDPEs ("LCB mLLDPEs") are considered to be long chain branched; however, their total long chain branching is still less than that of LDPEs with very high long chain branching. This small amount of LCB can be evidenced, for example, by a high melt index ratio (MIR) and / or specific rheological properties, such as data obtained by small angle oscillatory shear (SAOS) experiments (e.g., η 0.01 / η 100 Another useful parameter for indicating the presence of LCBs is the Van Gurp Palmen (VGP) plot, an example of which can be seen in Figure 3 of US 2022 / 0259417, which is incorporated herein by reference. In particular, polyethylene copolymers (even LLDPE) with some LCBs will show an inflection point in their VGP curves, while LLDPE without any LCBs will not show such an inflection point. See, for example, Enable plot in Figure 3 of US 2022 / 0259417. TMBrand LLDPE (an example of an LCB-mLLDPE), compared to XP8318 of FIG. 3 of the '417 publication (which is an example of a narrow-MWD BOCD-mLLDPE discussed below).

[0043] Another useful parameter that indicates the presence of some LCB can be seen in the melt index ratio. The melt index ratio (MIR) is the ratio of the high load melt index (HLMI, ASTM D1238, at 190°C, 21.6 kg) to the melt index (MI2, ASTM D1238, at 190°C, 2.16 kg).

[0044] Thus, LCB-mLLDPE useful in the compositions of the present invention may have one or more of the following properties (which may be useful markers of a medium LCB): The MIR ranges from a lower limit of any of 20, 25, 26, 27, 28, 29, 30, or 31 to an upper limit of any of 40, 35, 34, 33, 32, 31, or 30, with ranges from any of the foregoing lower limits to any of the foregoing upper limits contemplated herein (e.g., 27 to 33, such as 28 to 32 or 29 to 31). · The complex shear viscosity (η*) at 0.01 Rad / s and 190°C is in the range of 5,000 to 12,000 Pa·s; or from a lower limit of any one of 5,000; 6,000; 7,000; 8,000; 9,000; 10,000; or 11,000 Pa·s to an upper limit of any one of 12,000; 11,000; 10,000; 9,000; 8,000; 7,000; or 6,000 Pa·s, where ranges from any lower limit to any upper limit are contemplated (e.g., 6,000 Pa·s to 8,000 Pa·s). · The complex shear viscosity (η*) at 100 Rad / s and 190°C is in the range of 900 to 2000 Pa·s; for example, from a lower limit of any one of 900; 1,000; 1,100; or 1,200 Pa·s to an upper limit of any one of 1,200; 1,300; 1,400; 1,500; or 2,000 Pa·s, wherein ranges from any of the foregoing lower limits to any of the foregoing upper limits are also contemplated (e.g., 1,100 Pa·s to 1,300 Pa·s). The shear thinning ratio (η*@0.01 / 100) is less than 15, or is in the range of 3 to 15, or 4 to 12, or 5 to 10, or 5.5 to 8. • Inflection point in the van Gurp-Palmen plot of phase angle vs. complex modulus (Pa) for LCB-mLLDPE.

[0045] Finally, another indicator of LCB can be found in the LCB Index (g' or alternatively g'vis ), which for LCB-mLLDPE may be less than 1, such as in the range of 0.9 to 0.99 or 0.94 to 0.98, but still significantly higher than the g' of heavily-LCB polyethylene (e.g., LDPE prepared using free radical polymerization).

[0046] Suitable mLLDPEs having the above medium LCBs preferably contain from 80, 85, 88, 90, 92, 93, 94 or 95 to 6, 97, 98 or 99 wt % ethylene derived units, the remainder being derived from one or more C3 to C 12 Copolymers of α-olefins, in particular one or more of butene, hexene, octene, preferably one of these, more preferably hexene. The weight % is based on the total mass of ethylene-derived units plus comonomer-derived units in the polyethylene.

[0047] Suitable LCB mLLDPE may also have a CDBI greater than or equal to 60%, preferably greater than or equal to 70%, for example within the range of a lower limit of any of 60, 70 or 75% to an upper limit of 80, 85, 90, 95 or 99%, with ranges from any of the foregoing lower limits to any of the foregoing upper limits being contemplated. The Composition Distribution Breadth Index ("CDBI") is defined as the weight percentage of copolymer molecules having a comonomer content within + / - 50% of the median comonomer mol% value, as described on pages 18-19 of WO 1993 / 003093 in conjunction with Figure 17 therein. This means that for a copolymer having a median comonomer mol% value (Cmed) of 8 mol% comonomer on the polymer chain, the CDBI is the weight percentage of copolymer chains having a comonomer mol% between (0.5 x Cmed) and (1.5 x Cmed). In this example, CDBI is the weight percent of copolymer chains having a comonomer mol% between (0.5 x 8) and (1.5 x 8) or a comonomer content between 4 mol% and 12 mol%. WO 1993 / 003093 also describes the use of chromatography and C 13 For methods of determining the weight fraction vs. composition curve (i.e., composition distribution curve) of a polymer by NMR and determining the median comonomer composition Cmed therefrom, see Figures 16 and 17 of this publication. See also Wild et al., J. Poly. Sci., Poly. Phys. Ed., Vol. 20, p. 441 (1982) and U.S. Pat. No. 5,008,204, which are also incorporated herein by reference.

[0048] Suitable LCB mLLDPE may also have an MWD (Mw / Mn) in the range of 2.5 to 5.5, for example in the range of 3 or 3.5 to 4.5 or 5.

[0049] Suitable LCB mLLDPEs can further have a melt index (I2, measured according to ASTM D1238 at 190°C, 2.16 kg load) in the range of 0.1 to 3.0 g / 10 min, or can be in the range of from a lower limit of any of 0.1, 0.15, 0.2, or 0.22 to an upper limit of any of 0.30, 0.40, 0.50, 0.60, 0.70, 0.80, 0.90, 1.0, 1.5, 2.0, 2.2, 2.5, 2.7, or 3.0 g / 10 min; ranges from any of the foregoing lower limits to any of the foregoing upper limits (as long as the upper limit is greater than the lower limit) are also contemplated, for example, from 0.1 to 2.5 g / 10 min; from 0.15 to 1.0 g / 10 min; or from 0.2 to 0.50 g / 10 min.

[0050] High Load Melt Index (HLMI or I 21 , measured according to ASTM D1238 at 190° C., 21.6 kg load) can be in the range of 10 to 75 g / 10 min, for example, 12 to 70 g / 10 min.

[0051] The density of LCB-mLLDPE can be between 0.900 and 0.940 g / cm 3 In the range of 0.905, 0.910, 0.920 or 0.925 g / cm 3 The lower limit of any one of 0.930, 0.932, 0.933, 0.934, 0.935 or 0.940 g / cm 3 The upper limit of any of the foregoing lower limits is contemplated herein, and ranges from any of the foregoing lower limits to any of the foregoing upper limits are contemplated herein (e.g., 0.910 to 0.935 g / cm 3 ).

[0052] These LCB-mLLDPEs may be referred to as "first mLLDPEs" in the compositions described herein. Some specific examples of such first mLLDPEs having the aforementioned unique combination of properties include certain Enable TM and Exceed TM XP brand polyethylene, such as Exceed TM XP 6026, Enable TM 2010、Enable TM 2703、Enable TM 3505、Enable TM 4002 and Enable TM 4009 performance polyethylene. Other commercial examples include Dow Innate TM ST70, Dow AgilityTM 2001, Dow Elite TM 5940、Dowlex TM 2038.68G, Dow Elite TM AT 6401、Dow Attane TM 4701G、Mar lex TM TR130 and Nova Surpass TM 117 / 116. Narrow MWD BOCD-mLLDPE

[0053] In some embodiments, LLDPE can be prepared using a metallocene catalyst, which is a substituted bulky ligand hafnium transition metal metallocene catalyst compound and substituted versions thereof, as disclosed in U.S. Patent Nos. 9,181,362, 6,242,545, 7,078,467, RE40751 11,214.659, and 9,695,290; and U.S. Publication Nos. 2015 / 240000, 2015 / 259445, and 2015 / 284523, the contents of which are incorporated herein by reference in their entireties. Such catalysts can be used to produce polyethylene grades having narrow MWD and broad orthogonal comonomer distribution ("BOCD"), which may be referred to herein as narrow MWD BOCD-mLLDPE.

[0054] As described above, suitable mLLDPE can have a narrow molecular weight distribution (MWD) and a broad orthogonal composition distribution (BOCD). The molecular weight distribution (MWD) or (Mw / Mn) can be in the range of about 2.0 to about 4.5, about 2.2 to about 4.5, about 3.0 to about 4.0, or about 2.5 to about 4.0. The weight average molecular weight (Mw) can be about 15,000 to about 400,000 g / mol, about 20,000 to about 250,000 g / mol, about 20,000 to about 200,000 g / mol, about 25,000 to about 150,000 g / mol, about 150,000 to about 400,000 g / mol, about 200,000 to about 400,000 g / mol, or about 250,000 to about 350,000 g / mol. The ratio of the z-average molecular weight (Mz) to the weight average molecular weight (Mw) may be greater than about 1.5, or greater than about 1.7, or greater than about 2.0. In some embodiments, this ratio is from about 1.7 to about 3.5, from about 2.0 to about 3.0, or from about 2.2 to about 3.0.

[0055] The term "orthogonal comonomer distribution" is used herein to refer to the molecular weight range of a polymer, the comonomer content of the various polymer fractions being not substantially uniform and their higher molecular weight fractions generally having a higher comonomer content than lower molecular weight fractions. The term "substantially uniform comonomer distribution" is used herein to refer to the comonomer content of a polymer fraction varying by <10.0 weight % across the molecular weight range of a vinyl polymer. In some embodiments, substantially uniform comonomer distribution can refer to <8.0 weight %, <5.0 weight %, or <2.0 weight %. Substantially uniform and orthogonal comonomer distributions can be measured using fractionation techniques such as gel permeation chromatography-differential viscometry (GPC-DV), temperature rising elution fractionation-differential viscometry (TREF-DV) or cross fractionation techniques.

[0056] The width of the composition distribution of the polymer can be determined by T 75 -T 25 Characterization. TREF was measured using an analytical size TREF instrument (Polymerchar, Spain) having a column with the following dimensions: internal diameter (ID) 7.8 mm, outer diameter (OD) 9.53 mm and column length 150 mm. The column can be packed with steel balls. 0.5 mL of a 4 mg / ml polymer solution in o-dichlorobenzene (ODCB) containing 2 g BHT / 4 L was fed to the column and cooled from 140° C. to -15° C. at a constant cooling rate of 1.0° C. / min. Subsequently, ODCB can be pumped through the column at a flow rate of 1.0 ml / min and the column temperature can be increased at a heating rate of 2° C. / min to elute the polymer. The elution temperature at 2941 cm -1 The concentration of the polymer in the eluted liquid is determined by the absorbance at a wave number of . The concentration of the ethylene-α-olefin copolymer in the eluted liquid can be calculated from the absorbance and plotted as a function of temperature. The T used herein is 75 -T 25 The value is where T 25 is the temperature in degrees Celsius at which 25% of the eluted polymer is obtained via TREF analysis, T 75 is the temperature in degrees Celsius at which 75% of the eluted polymer is obtained.

[0057] "Broad Orthogonal Comonomer Distribution" or BOCD means that there is a much higher degree of short chain branching on the longer molecular weight polymer chains than on the shorter molecular weight polymer chains within the copolymer. Suitable narrow-MWD mLLDPE with BOCD may have a T of 5 to 10. 75 -T 25 value, or T of 5.5 to 10 75 -T 25 value, or T of 5.5 to 875 -T 25 value, or T of 6 to 10 75 -T 25 value, or T of 6 to 8 75 -T 25 value, where T 25 is the temperature in degrees Celsius at which 25% of the eluted polymer is obtained, T 75 is the temperature in degrees Celsius at which 75% of the eluted polymer is obtained via temperature rising elution fractionation (TREF).

[0058] These mLLDPEs may have a CDBI of less than about 40%, or less than about 35%, or less than about 30%, or less than about 25%. The CDBI may also range from a low of about 15%, 20%, or 25% to an upper limit of about 30%, 35%, or 40%, and further noting that the composition distribution is such that the higher molecular weight chains of these mLLDPEs have a greater weight % of comonomer than the lower molecular weight chains of the mLLDPE.

[0059] These mLLDPEs may have between 70.0% and 100.0% by weight of units derived from ethylene. The lower end of the ethylene content range, based on the weight of the polymer units derived from ethylene, may be 70.0%, 75.0%, 80.0%, 85.0%, 90.0%, 92.0%, 94.0%, 95.0%, 96.0%, 97.0%, 98.0%, or 99.0%. These mLLDPEs may also have an upper end of 80.0%, 85.0%, 90.0%, 92.0%, 94.0%, 95.0%, 96.0%, 97.0%, 98.0%, 99.0%, 99.5%, or 100.0% by weight of ethylene, based on the weight of the polymer units derived from ethylene. Less than 30.0 wt. % of the polymer units may be derived from C3-C 20 Olefins, preferably α-olefins, such as hexene or octene. Based on 20 Polymer units of olefins, C3-C 20 The lower end of the range of olefin content can be 25.0 wt%, 20.0 wt%, 15.0 wt%, 10.0 wt%, 8.0 wt%, 6.0 wt%, 5.0 wt%, 4.0 wt%, 3.0 wt%, 2.0 wt%, 1.0 wt%, or 0.5 wt%. 20 Polymer units of olefins, C3-C 20The upper limit of the range of olefin content can be 20.0 wt%, 15.0 wt%, 10.0 wt%, 8.0 wt%, 6.0 wt%, 5.0 wt%, 4.0 wt%, 3.0 wt%, 2.0 wt%, or 1.0 wt%.

[0060] These mLLDPEs may have a g / cm 3 to about 0.940 g / cm 3 , about 0.910g / cm 3 to about 0.935g / cm 3 , about 0.900g / cm 3 to about 0.930 g / cm 3 , about 0.900g / cm 3 to about 0.925g / cm 3 , about 0.900g / cm 3 to about 0.923 g / cm 3 , about 0.900g / cm 3 to about 0.920g / cm 3 , about 0.912g / cm 3 to about 0.919 g / cm 3 , about 0.912g / cm 3 to about 0.918 g / cm 3 , about 0.914g / cm 3 to about 0.918 g / cm 3 or about 0.915 g / cm 3 to about 0.918 g / cm 3 Density according to ASTM D-4703 and ASTM D-1505 / ISO 1183.

[0061] These mLLDPEs may have a viscosity as measured by ASTM D-1238-E (190° C. / 2.16 kg) of about 0.1 g / 10 min to about 5.0 g / 10 min, about 0.1 g / 10 min to about 3.0 g / 10 min, about 0.1 g / 10 min to about 2.0 g / 10 min, about 0.1 g / 10 min to about 1.2 g / 10 min, about 0.2 g / 10 min to about 1.5 g / 10 min, about 0.2 g / 10 min to about 1.1 g / 1 0 min, about 0.3 g / 10 min to about 1.0 g / 10 min, about 0.4 g / 10 min to about 1.0 g / 10 min, about 0.5 g / 10 min to about 1.0 g / 10 min, about 0.6 g / 10 min to about 1.0 g / 10 min, about 0.7 g / 10 min to about 1.0 g / 10 min, or about 0.75 g / 10 min to about 0.95 g / 10 min of melt index (MI) or (I 2.16 ).

[0062] These mLLDPEs may have a melt index ratio (MIR) (I 21.6 / I 2.16 )(as defined below).

[0063] These mLLDPEs may also have at least a first peak and a second peak in a comonomer distribution analysis, wherein the first peak is between 4.0 and 5.4, or between 4.3 and 5.0, or between 4.5 and 4.7 log(M w ) value and a TREF elution temperature of 70.0°C to 100.0°C, or 80.0°C to 95.0°C, or 85.0°C to 90.0°C. The second peak in the comonomer distribution analysis has a maximum at a log(Mw) value of 5.0 to 6.0, 5.3 to 5.7, or 5.4 to 5.6, and a TREF elution temperature of 40.0°C to 60.0°C, 45.0°C to 60.0°C, or 48.0°C to 54.0°C.

[0064] In any of the above embodiments, suitable mLLDPE can have a narrow MWD, a broad orthogonal composition distribution, and one or more of the following properties: a melt index (MI) of about 0.1 g / 10 min to about 5.0 g / 10 min (190° C. / 2.16 kg); a melt index ratio (MIR) of about 25 to about 32; an MIR of about 20,000 to about 200,000 g / mol; w ; M from about 2.0 to about 4.5 w / M n ; and about 0.900g / cm 3to about 0.940 g / cm 3 density.

[0065] Commercially available examples of such second mLLDPEs having the aforementioned unique combination of properties include Exceed XP from ExxonMobil Chemical Company. TM Resin. Wide-BOCD-mLLDPE

[0066] In some embodiments, LLDPE can be prepared using a dual metallocene catalyst system comprising a bridged biscyclopentadienyl Group 4 metal catalyst and an unbridged biscyclopentadienyl Group 4 metal catalyst, as disclosed in one or more of U.S. Patent Nos. 10,611,867, 10,808,053, and 11,274,196; WIPO Publication No. WO2019 / 108327; and U.S. Publication No. 2021 / 0238321, the contents of which are incorporated herein by reference in their entirety (and which further include descriptions of related mLLDPE). Such catalyst systems can produce polyethylene grades with broad MWD and broad orthogonal comonomer distribution ("BOCD"), referred to herein as "broad-BOCD-mLLDPE."

[0067] The MWD (weight average molecular weight Mw divided by number average molecular weight Mn) of these mLLDPEs can range, for example, from about 6.0 to about 10.0, from about 6.4 to about 9.5, from about 6.0 to about 9.0, from about 6.5 to about 10.0, or from 7.0 to 8.5.

[0068] These mLLDPEs may have a g / cm 3 to about 0.945g / cm 3 , for example, about 0.910 g / cm 3 to about 0.935g / cm 3 , about 0.910g / cm 3 to about 0.930 g / cm 3 , about 0.900g / cm 3 to about 0.925g / cm 3 , about 0.900g / cm 3 to about 0.933 g / cm 3 , about 0.900g / cm 3 to about 0.920g / cm 3 , about 0.912g / cm 3 to about 0.919 g / cm 3 , about 0.912g / cm 3 to about 0.938 g / cm 3 , about 0.914g / cm3 to about 0.928 g / cm 3 or about 0.915 g / cm 3 to about 0.938 g / cm 3 Any of the foregoing lower limits may be combined with any of the foregoing upper limits, provided that the upper limit is greater than the lower limit (e.g., 0.912 to 0.915 g / cm 3 , or 0.910 to 0.928 g / cm 3 ).

[0069] These mLLDPEs may have g' vis A branching index (as defined herein) of ≥0.95, ≥0.96, ≥0.97, ≥0.98, ≥0.99 or 1.0, e.g., from 0.95 to 1.0, from 0.96 to 1.0, from 0.97 to 0.995, from 0.98 to 0.998, from 0.98 to 0.99, from 0.99 to 1.0. Preferably, g' vis ≥0.98 or ≥0.995.

[0070] Suitable broad MWD BOCD-mLLDPE may have a T 75 -T 25 BOCD values ​​of 15°C or higher, 17.5°C or higher, 20°C or higher, 25°C or higher, 30°C or higher, 35°C or higher, 40°C or higher, or 45°C or higher, wherein T 25 is the temperature (°C) at which 25% of the eluted polymer is obtained in the TREF experiment, and T 75 is the temperature (°C) at which 75% of the eluted polymer is obtained in the TREF experiment. For example, the T 75 -T 25 Values ​​may range from 30°C or 35°C to 55°C, 55°C, 60°C, or 65°C (ranges from any foregoing lower limit to any foregoing upper limit being contemplated).

[0071] These mLLDPEs may have a CDBI of less than about 40%, or less than about 35%, or less than about 34%, or less than about 33%. The CDBI may also range from a lower limit of about 15%, 20%, or 25% to an upper limit of about 35%, 37%, or 40%, and the composition distribution (or comonomer distribution) is such that the mLLDPE has a greater amount (wt %) of comonomer incorporated in its longer (higher molecular weight) polymer chains than in its shorter (lower molecular weight) polymer chains. As already noted, GPC analysis methods are suitable for determining the relative amounts of comonomer incorporation at high and low polymer chains. For examples of some such polymers and a discussion of comonomer incorporation along their chains, see, for example, PCT / US2021 / 072552, entitled "Medium Density Polyethylene Compositions with Broad Orthogonal Composition Distribution," filed on November 22, 2021, and hereby incorporated by reference. Modifier

[0072] The modifier is preferably an ethylene copolymer elastomer modifier. The modifier comprises at least 70 wt% ethylene derived units (e.g., within the range of 70, 71, or 72 wt% to 78, 79, or 80 wt% ethylene derived units) and 20-30 wt% (e.g., 21, 22, 23, or 24 wt% to 25, 26, 27, 28, 29, or 30 wt%) of C3 to C6 derived units. 20 (Preferably C3 to C 10 ) α-olefin comonomer (e.g., propylene). Preferred modifiers of some embodiments may be, for example, ethylene-propylene (EP) elastomeric copolymers. In other embodiments, the modifier optionally further comprises from 0.1 to 5 weight percent of units derived from a cyclic-diene comonomer, such that the modifier of such embodiments may be, for example, an ethylene terpolymer elastomer, with preferred examples of such embodiments including EPDM (ethylene-propylene-diene monomer) elastomers, such as those derived from ethylene, propylene, and a cyclic-diene.

[0073] The diene may be conjugated or non-conjugated. For example, the non-conjugated diene may be 5-ethylidene-2-norbornene (ENB); 1,4-hexadiene; 5-methylene-2-norbornene (MNB); 1,6-octadiene; 5-methyl-1,4-hexadiene; 3,7-dimethyl-1,6-octadiene; 1,3-cyclopentadiene; 1,4-cyclohexadiene; 5-vinyl-2-norbornene (VNB); dicyclopentadiene (DCPD), and combinations thereof. For example, the diene, if present, is preferably ENB and / or VNB.

[0074] In some embodiments employing a cyclic diene, the cyclic diene monomer is selected from dicyclopentadiene (DCPD), norbornadiene (NBD), 5-vinyl-2-norbornene (VNB), ethylidene norbornene (ENB), derivatives thereof, and combinations thereof, or is VNB.

[0075] In some embodiments, the α-olefin comonomer units may be derived from propylene, 1-butene, 1-hexene, and / or 1-octene; preferably the comonomer units are propylene.

[0076] Therefore, some embodiments of the modifier may include a C-C- 20 Units of an α-olefin comonomer and, optionally, one or more cyclic-diene comonomers, such that the α-olefin comonomer-derived units are present in a range of 20-30 wt % (e.g., 20, 21, 22, 23, or 24 wt % to 25, 26, 27, 28, 29, or 30 wt %); the cyclic-diene comonomer-derived units are present in a range of 0 to 5 wt % (e.g., 0, 0.1, 0.2, 0.3, or 0.5 to 1, 1.5, 2, 2.5, 3, 4, or 5 wt %); the balance being ethylene-derived units (all wt % are based on the total molecular weight of the modifier). Ranges from any of the foregoing lower limits to any of the foregoing upper limits are contemplated (e.g., 21 to 25 wt % α-olefin comonomer-derived units; 0.1 to 5 wt % cyclic-diene comonomer-derived units). For example, the modifier can be an ethylene copolymer elastomer modifier having 70-80 wt% ethylene derived content, 20-30 wt% C3 to C 10 α-olefin comonomer derived content and optionally 0.1 to 5 wt % (e.g., 0.1 to 1 wt % or 2 wt %) cyclic-diene comonomer derived content.

[0077] The distribution of monomers in the modifier may be random, but it is also contemplated that the modifier may have a block content that is dependent upon the monomer distribution.

[0078] The modifier may have a viscosity of about 0.85 g / cm 3 to about 0.926 g / cm 3 , about 0.85g / cm 3 to about 0.923 g / cm 3 , or about 0.87g / cm 3 to about 0.91g / cm 3 , for example, about 0.88 g / cm 3The density of the modifier is determined using chips cut from plaques compression molded according to ASTM D-1928, Procedure C, aged according to ASTM D-618, Procedure A, and measured as specified in ASTM D-1505.

[0079] The modifier preferably has long chain branching.The presence of long chain branching can be inferred from various rheological and / or viscosity parameters.

[0080] For example, the modifier can be characterized according to its Mooney viscosity units (test methods and further details are described below in conjunction with the "Modifier Test Methods" section); for example, it can have one or more of the following properties: (i) a Mooney viscosity in the range of 10 to 40 MU (ML, 1+4 @ 100°C), for example, in the range of 10, 12, 14, 16, 18, or 20 MU to 25, 27, 28, 29, 30, 32, 35, 37, or 40 MU; (ii) a Mooney relaxation area (MLRA) in the range of 100 to 500 MU-sec, for example, in the range of 100, 130, 150, 175, or 200 MU-sec to 250, 300, 350, 400, 450, or 500 MU-sec; and (iii) a corrected Mooney relaxation area (cMLRA) of 400 MU-sec or greater, 600, 800, or 1000 MU-sec or greater.

[0081] Additionally, or alternatively, the modifier can be characterized based on its rheological properties. For example, in various embodiments, the modifier can have one or more of the following properties: ·In complex modulus G*=10 5 The phase angle (also called loss angle) δ measured at Pa is in the range of 15-45°, such as 20° to 30°, 35°, 40° or 45°, or 0-45° (i.e., 45° or less) or 0-35° (i.e., 35° or less); Tan (δ) of 0.9 or less, 0.8 or less, 0.6 or less, 0.5 or less, or 0.4 or less (measured at a frequency of 0.245 Rad / s); in other embodiments, Tan (δ) may range from 0.400 to 0.800, for example, from a lower limit of any one of 0.400, 0.425, or 0.430 to an upper limit of any one of 0.500, 0.550, 0.575, 0.600, 0.650, 0.675, 0.700, 0.750, or 0.800; STR (shear thinning ratio, η*(0.1 Rad / s) / η*(128 Rad / s)) is in the range of 50 to 500, preferably 100 to 400, for example in the range of any one of 50, 75 or 100 to 200, 250, 300, 350, 400, 450 or 500.

[0082] Still further, long chain branching in the modifier can be seen by a van Gurp-Palmen (VGP) plot of loss angle vs. G*, such as that shown in Figure 6 of US2020 / 0223951, which is incorporated herein by reference. In this figure, examples of three ethylene-propylene-optional diene copolymers of modifiers according to the present disclosure can be seen, all of which have a plateau in the VGP plot, which is characteristic of long chain branching.

[0083] Optionally, the modifier may be further characterized based on its molecular weight characteristics; in particular, the modifier may include any one or more of the following properties: a number average molecular weight (Mn), preferably determined by GPC-IR as described below, in the range of 8,000 to 70,000 g / mol, preferably 10,000 to 40,000 g / mol, for example 8,000; 10,000; or 12,000 g / mol to 15,000; 17,500; 20,000; 22,500; 25,000; 30,000; 40,000; 50,000; 60,000; or 70,000 g / mol, wherein ranges from any of the foregoing lower limits to any of the foregoing upper limits are contemplated. a weight average molecular weight (Mw), preferably determined by GPC-LS as described below, in the range of 100,000 g / mol to 800,000 g / mol, preferably 120,000 g / mol to 500,000 g / mol, for example from a lower limit of any of 100,000; 115,000; 120,000; or 125,000 g / mol to an upper limit of any of 175,000; 200,000; 225,000; 250,000; 275,000; 300,000; 350,000; 400,000; 450,000; 500,000; 600,000; 700,000 or 800,000 g / mol, with ranges from any of the foregoing lower limits to any of the foregoing upper limits being contemplated. Z-average molecular weight (Mz), preferably also determined by GPC-LS, in the range of 300,000 to 3,000,000 g / mol, preferably 325,000 to 2,800,000 g / mol; for example, in the range of 300,000; 325,000; 350,000; or 400,000 g / mol, to an upper limit of 500,000; 750,000; 1,000,000; 1,500,000; 2,000,000; 2,500,000; 2,800,000; or 3,000,000 g / mol, with ranges from any of the foregoing lower limits to any of the foregoing upper limits being contemplated. Molecular weight distribution (MWD, M WLS / M nIR ) is in the range of 5, 6, 7 or 8 to 11, 12, 15, 20 or 30.

[0084] The ethylene α-olefin diene terpolymers of the present disclosure can be prepared by any suitable polymerization process (including solution polymerization, slurry polymerization and gas phase polymerization) using a supported or unsupported catalyst system, such as a system comprising a metallocene catalyst. Non-limiting examples of metallocene catalysts and catalyst systems include those described in U.S. Patent No. 7,511,106, which is incorporated herein by reference in its entirety.

[0085] In at least one embodiment, a procedure suitable for preparing ethylene alpha-olefin diene terpolymers is as follows. The catalyst used is VOCl3 (vanadium oxytrichloride) or VCl4 (vanadium tetrachloride). The cocatalyst is selected from (i) ethylaluminum sesquichloride (SESQUI), (ii) diethylaluminum chloride (DEAC), and (iii) an equivalent mixture of diethylaluminum chloride and triethylaluminum (TEAL). As shown in U.S. Patent No. 5,763,533 (Figure 8), the choice of cocatalyst affects the composition distribution in the polymer. Elastomers with a wider composition distribution are expected to provide better tensile strength in cable coating compounds. Polymerization is carried out in a continuously stirred tank reactor at 20-65°C with a residence time of 6-15 minutes and a pressure of 7 kg / cm 2The pressure is carried out. The concentration ratio of vanadium to alkyl is 1:4 to 1:8. Each gram of catalyst fed into the reactor produces about 0.3 to 1.5 kg of polymer. The polymer concentration in the hexane solvent is 3-7 weight %. As reported in US 5,763,533, the synthesis of ethylene, α-olefins, and vinyl norbornene polymers is carried out in a laboratory pilot plant (output of about 4 kg / day), a large-scale pilot plant (semi works) plant (output 1T / day), and an industrial-scale production plant (output 200,000 kg / day). The modifier useful in the present invention can be prepared by any suitable method, but in any embodiment, the method used in US 7,511,106 is used, most preferably a solution metallocene process. Examples of commercially available modifiers include certain Vistalon from ExxonMobil Chemical Company. TM EPDM grades, especially those with VNB-derived content, such as Vistalon TM 1703P EPDM. More generally, such embodiments of the modifier can be characterized as ethylene-propylene-diene copolymers having a VNB-derived content.

[0086] In yet other embodiments, the modifier can be an ethylene-propylene copolymer and substantially free of diene-derived units (e.g., free of VNB, ENB, etc.), or can be an ethylene-propylene-diene copolymer having ENB-derived units but substantially free of VNB-derived units. Specific examples of such EP elastomeric copolymers are described as "low Mooney copolymer compositions" in US 2020 / 0223951; and for a discussion of suitable methods for preparing such elastomeric copolymers, reference is made to paragraphs

[0101] -

[0118] of that publication (which description is incorporated herein by reference). Test and measurement methods for modifiers

[0087] Some measurement methods of modifiers may be different from those used in combination with the above-mentioned polyethylene polymers. Unless otherwise stated, the measurement method of the modifier described herein should be determined by following the description of paragraphs

[0136] -

[0162] of US2020 / 0223951, which is incorporated herein by reference. In addition, in the context of modifiers, a modification of the test method as described herein should also be used: in the case where DRI, IR and / or LS measurements conflict, LS measurements are applied to Mw and Mz, and DRI or IR measurements are applied to Mn (if not specified for Mn, IR measurement is used). Also, although MWD (polydispersity) is taken as Mw / Mn, in the case where DRI, LS and / or IR measurements conflict, MWD should be determined as Mw (measured by LS) / Mn (measured by IR), or M wLS / M nIR . Modified polyethylene

[0088] In at least one embodiment, the method of the present disclosure produces a modified polyethylene comprising a first polyethylene and a second polyethylene. The modified polyethylene is the product of a combination of 90-99.9 % by weight of a polyethylene and 0.10-10 % by weight of a modifier, wherein the weight percentages are based on the gross weight of the polyethylene and the modifier. Preferably, the amount of the modifier is present in the modified polyethylene in an amount ranging from a lower limit of 0.2, 0.3 or 0.5 % by weight to an upper limit of 1.0, 1.25, 1.5, 1.75, 2.0, 2.5, 3 or 5 % by weight, wherein considering the range from any aforementioned lower limit to any aforementioned upper limit.

[0089] In at least one embodiment, the melt strength of the modified polyethylene can be from about 1 to about 100 cN, from about 1 to about 50 cN, from about 1 to about 25 cN, from about 3 to about 15 cN, from about 4 to about 12 cN, or from about 5 to about 10 cN, or from about 5 to about 15 cN when measured at 190° C. In some embodiments, the modified polyethylene has a melt strength of at least about 5 cN, at least about 10 cN, or at least about 15 cN, and up to about 20 cN when measured at 190° C.

[0090] The compositions of the present disclosure can be prepared by mixing a first polyethylene polymer with an ethylene α-olefin diene terpolymer, by connecting reactors together in series to prepare a reactor blend, or by using more than one catalyst in the same reactor to prepare multiple polymers. The polymers can be mixed together before being fed into the extruder or the polymers can be mixed in the extruder.

[0091] The composition can be formed by dry blending the polymers and then melt mixing them in a mixer, or by mixing the polymers together directly in a mixer such as a Banbury mixer, a Haake mixer, a Brabender internal mixer, or a single or twin screw extruder, which can include a compounding extruder and a side arm extruder used directly downstream of the polymerization process, which can include blending powders or pellets of the resin at the hopper of a film extruder. In addition, additives can be included in the composition, in one or more components of the composition, and / or in a product formed from the composition, such as a film, as desired. These additives can include, for example: fillers; antioxidants (e.g., hindered phenolic compounds such as IRGANOX® available from BASF); TM 1010 or IRGANOX TM 1076); phosphites (e.g., IRGAFOS available from BASF TM168); anti-adhesive additives; tackifiers such as polybutene, terpene resins, aliphatic and aromatic hydrocarbon resins, alkali metal and glycerol stearates, and hydrogenated rosin; UV stabilizers; heat stabilizers; antiblocking agents; release agents; antistatic agents; pigments; colorants; dyes; waxes; silica; fillers, and talc.

[0092] The production of modified polyethylene comprises the extrusion of molten composite, and described molten composite is the mixture or the blend of polyethylene and properties-correcting agent.When mentioning " polyethylene ", " properties-correcting agent " or " molten composite ", this comprises the possibility of the blend with two or more polymers and / or properties-correcting agent that meet this description.They can be blended together by any known method, for example the dry blending of the pellet / particle of material, then melt extrusion is to form the uniform blend that is suitable for forming blown film, foamed articles such as plate and cup and other useful articles.Blending can be carried out before forming film or other articles, thereby forming pellet or the particle of the blend that can be transported and / or stored, or blending can be carried out in the melt blending equipment (for example screw extruder) for film forming or foamed articles processing equipment.In any stage, other additives commonly used in this area, for example antioxidant, slipping agent etc. can also be added.

[0093] In another aspect, the modified polyethylene can be blended in solution by any suitable means using a solvent that dissolves the two components to a significant extent. Blending can be carried out at any temperature or pressure where the modifier and the polyethylene polymer are kept in solution. Conditions include blending at high temperatures, such as 10°C or more, such as 20°C or more, higher than the melting point of the polyethylene polymer. Such solution blending will be particularly suitable for methods in which the polyethylene polymer is prepared by a solution process and the modifier is added directly to a finishing train rather than being added together to the dry polymer in another blending step. Such solution blending is also particularly suitable for methods in which the polyethylene polymer is prepared in bulk or high pressure processes, where both the polymer and the modifier are soluble in monomers. As with the solution process, the second polyethylene is added directly to the finishing train rather than being added together to the dry polymer in another blending step.

[0094] Thus, in the case of manufacturing articles using a process involving an extruder (e.g., injection molding or blow molding), any method of combining the first polyethylene polymer and the second polyethylene polymer to obtain the desired composition is as good as fully formulated pre-blended pellets, since the forming process can include remelting and mixing of the raw materials; exemplary combinations include neat polymer pellets (and optional additive(s)), neat polymer granules, and simple blends of neat polymer pellets and pre-blended pellets. Here, "pre-blended pellets" refers to pellets of modified polyethylene. However, in compression molding processes, little mixing of the molten components occurs, and pre-blended pellets will be preferred over simple blends of the component pellets (or granules). Those skilled in the art will be able to determine the appropriate procedure for blending the polymers to balance the need for uniform mixing of the constituent components with the desire for process economy. End Use

[0095] Any of the above polymers and compositions, in combination with optional additives (see, e.g., U.S. Patent Application Publication No. 2016 / 0060430, paragraphs

[0082] -

[0093] ), can be used in a variety of end-use applications. Such end-uses can be produced by methods known in the art. End-uses include polymer products and products with specific end-uses. Exemplary end-uses can include, but are not limited to, films, film-based products, diaper backsheets, industrial filter cloths, wire and cable coating compositions, articles formed by molding techniques such as injection molding or blow molding, extrusion coating, foaming, casting, and combinations thereof. End-uses also include products made from films, e.g., bags, packaging, and personal care films, pouches, medical products, such as medical films and intravenous (IV) bags. Membrane performance

[0096] The present inventors have discovered that films from blends of certain polyethylenes and certain modifiers exhibit a new and useful balance of properties, including, but not limited to, increasing the maximum throughput of a film production facility by as much as 15% or more, while maintaining or improving other film properties of the polyethylene, such as stiffness, tear resistance, tensile strength, and sealability, wherein the modifier is added to the polyethylene at 10% or less of the total composition. In addition, optical properties of the polyethylene, such as haze, are significantly improved by the addition of the modifier at 10% or less of the total composition. The following comparison of performance characteristics is based on a comparison of a given film production process using the modified polyethylene with the same film production process using the corresponding neat polyethylene. The corresponding neat polyethylene corresponding to a particular modified polyethylene means the polyethylene that would produce the modified polyethylene when blended with the specified amount of the modifier.

[0097] In some embodiments, film production rates are increased by 1% or more, 5% or more, 10% or more, 20% or more, 30% or more, 40% or more, or 50% or more when comparing neat polyethylene to the corresponding modified polyethylene, while maintaining or improving other film properties, such as stiffness, tear resistance, tensile strength, and sealing performance.

[0098] In some embodiments, independently or in combination with the above-mentioned film parameters, the haze of a film made from the modified polyethylene measured according to ASTM D-1003 is 80% or less, 60% or less, 40% or less, or 20% or less of the haze measured for the same film made from the corresponding pure polyethylene.

[0099] In some embodiments, independently or in combination with the above-mentioned film parameters, the strength set ratio (SHR) of a film made from the modified polyethylene is 1% or greater, 5% or greater, 10% or greater, 20% or greater, 30% or greater, 40% or greater, or 50% or greater than the SHR of the same film made from the corresponding neat polyethylene.

[0100] In some embodiments, independently or in combination with the above-mentioned film parameters, films made from the modified polyethylene have a puncture force that is 90% or greater, 95% or greater, 97% or greater, 99% or greater, or 100% of the value measured for a film produced by the same blown film extrusion process using neat polyethylene instead of the modified polyethylene.

[0101] In some embodiments, independently or in combination with the above film parameters, films made from the modified polyethylene have a puncture break energy according to modified ASTM D5748 that is 90% or greater, 95% or greater, 97% or greater, 99% or greater, or 100% of the value measured for a film produced by the same blown film extrusion process using virgin polyethylene instead of the modified polyethylene.

[0102] In some embodiments, independently or in combination with the above-mentioned film parameters, a film made from the modified polyethylene has an average TD 1% secant modulus (M) according to ASTM D882 that is 1% or more, 5% or more, 10% or more, 20% or more, 30% or more, 40% or more, or 50% or more greater than the average TD 1% secant modulus (M) of the same film made from the corresponding neat polyethylene.

[0103] In some embodiments, independently or in combination with the above-mentioned film parameters, films made from the modified polyethylene have an average MD 1% secant modulus (M) according to ASTM D882 that is 1% or more, 5% or more, 10% or more, 20% or more, 30% or more, 40% or more, or 50% or more greater than the average MD 1% secant modulus (M) of the same film made from the corresponding neat polyethylene.

[0104] In some embodiments, independently or in combination with the above-mentioned film parameters, the MD Elmendorf Tear Strength according to ASTM D1922 of a film made from the modified polyethylene is 1% or more, 5% or more, 10% or more, 20% or more, 30% or more, 40% or more, or 50% or more greater than the MD Elmendorf Tear Strength of the same film made from the corresponding neat polyethylene.

[0105] In some embodiments, independently or in combination with the above-mentioned film parameters, films made from the modified polyethylene have a dart drop impact (or dart drop F50 or dart drop impact strength (DIS), reported in grams (g) or grams per mil (g / mil) according to ASTM D1709, Method A) that is 90% or more, 95% or more, 100% or more, 110% or more, or 120% or more of the dart drop value measured for the same film made from the corresponding virgin polyethylene. Test Method

[0106] The properties cited herein were determined according to the following test procedures (except to the extent that the following procedure conflicts with the procedure described above for a modifier, the test method for the modifier shall apply to determining the property of the modifier).

[0107] Unless otherwise stated, molecular weight (M) was determined by using a high temperature gel permeation chromatography (Polymer Char GPC-IR) equipped with a multi-channel bandpass filter based infrared detector IR5, an 18-angle light scattering detector and a viscometer. w 、M n 、M w / M n etc., unless otherwise stated, reported in g / mol) distribution and fraction (moment), comonomer content (C2, C3, C6, etc.) and branching index (g' vis). Three Agilent PLgel 10μm mixed-B LS columns were used to provide polymer separation. Aldrich reagent grade 1,2,4-trichlorobenzene (TCB) containing 300ppm of the antioxidant butylated hydroxytoluene (BHT) was used as the mobile phase. The TCB mixture was filtered through a 0.1μm Teflon filter and degassed with an online degasser before entering the GPC instrument. The nominal flow rate was 1.0ml / min and the nominal injection volume was 200μL. The entire system including the transfer line, column and detector was loaded into an oven maintained at 145°C. The polymer sample was weighed and sealed in a standard vial, to which 80μL of flow marker (heptane) was added. After the vial was loaded into the autosampler, the polymer automatically dissolved in the instrument with 8mL of added TCB solvent. The polymer was dissolved at 160°C while continuously shaking for approximately 1 hour (for most PE samples). The TCB density used for concentration calculations was 1.463 g / ml at room temperature and 1.284 g / ml at 145°C. The sample solution concentrations were 0.2-2.0 mg / ml, with lower concentrations used for higher molecular weight samples. The concentration (c) of each point in the chromatogram was calculated from the IR5 broadband signal intensity (I) minus the baseline using the following equation: c=βI, where β is the mass constant. Mass recovery was calculated from the ratio of the integrated area of ​​the concentration chromatogram to the elution volume and the injected mass was equal to the predicted concentration multiplied by the injection loop volume. The conventional molecular weight (IRMW) was determined by combining a universal calibration relationship with a column calibration using a series of monodisperse polystyrene (PS) standards ranging from 700-10 M gm / mole. The MW at each elution volume was calculated using the following equation: Variables with the subscript "PS" represent polystyrene, while those without the subscript represent the test sample. In this method, α ps =0.67 and K PS =0.000175, and α and K are other materials as calculated and disclosed in the literature (Sun, T. et al. Macromolecules 2001, 34, 6812), except that for the purpose of this disclosure, for linear ethylene polymers, α=0.695 and K=0.000579, for linear propylene polymers, α=0.705 and K=0.0002288, for linear butene polymers, α=0.695 and K=0.000181, and for ethylene-butene copolymers, α = 0.695 and K is 0.000579 × (1 - 0.0087 × w2b + 0.000018 × (w2b) 2 ),That Where w2b is the gross weight percent of butene comonomer, for ethylene-hexene copolymers, α is 0.695 and K is 0.000579×(1-0.0075×w2b), where w2b is the gross weight percent of hexene comonomer, and for ethylene-octene copolymers, α is 0.695 and K is 0.000579×(1-0.0077×w2b), where w2b is the gross weight percent of octene comonomer. Unless otherwise stated, concentrations are in g / cm 3 The molecular weight is expressed in g / mole and the intrinsic viscosity (hence K in the Mark-Houwink equation) is expressed in dL / g.

[0108] The comonomer composition is determined by the ratio of the IR5 detector intensities corresponding to the CH2 and CH3 channels calibrated with a series of PE and PP homo / copolymer standards, the nominal values ​​of which were previously determined by NMR or FTIR. Specifically, this provides the methyl groups per 1000 total carbons (CH3 / 1000TC) as a function of molecular weight. The short chain branch ("SCB") content per 1000TC ("SCB / 1000TC") as a function of molecular weight is then calculated as follows: a chain end correction is applied to the CH3 / 1000TC functional groups, assuming that each chain is linear and terminated with a methyl group at each end. The comonomer weight % is then obtained by the following expression, where f is 0.3, 0.4, 0.6, 0.8, etc. for the C3, C4, C6, C8, etc. comonomers, respectively: w2=f*SCB / 1000TC The bulk composition of the polymer from GPC-IR and GPC-4D analysis was obtained by considering all signals of the CH3 and CH2 channels between the integration limits of the concentration chromatogram. First, the following ratio was obtained: Then, the same calibration of the CH2 and CH3 signal ratios as previously mentioned in obtaining CH3 / 1000TC as a function of molecular weight is applied to obtain bulk CH3 / 1000TC. Bulk methyl chain ends / 1000TC ("bulk CH3 ends / 1000TC") are obtained by weight averaging the chain end correction over the molecular weight range. w2b=f*body CH3 / 1000TC Body SCB / 1000TC=body CH3 / 1000TC-body CH3 end / 1000TC and the body SCB / 1000TC is converted into body w2 using the same method as above.

[0109] The LS detector was an 18-angle Wyatt Technology High Temperature DAWN HELEOS II. The LS molecular weight (M) at each point in the chromatogram was determined by analyzing the LS output using the Zimm model of static light scattering (Light Scattering from Polymer Solutions; Huglin, MB, Ed.; Academic Press, 1972.): Here, ΔR(θ) is the excess Rayleigh scattering intensity measured at the scattering angle θ, c is the polymer concentration determined by IR5 analysis, A2 is the second virial coefficient, p(θ) is the shape factor of the monodisperse random coil, and K o is the optical constant of the system: where N A is Avogadro's constant, and (dn / dc) is the refractive index increment of the system. The refractive index of TCB at 145°C and λ = 665 nm is n = 1.500. For the analysis of polyethylene homopolymer, ethylene-hexene copolymer, and ethylene-octene copolymer, dn / dc = 0.1048 ml / mg and A2 = 0.0015; for the analysis of ethylene-butene copolymer, dn / dc = 0.1048 × (1 - 0.00126 × w2) ml / mg and A2 = 0.0015, where w2 is the weight percent of butene comonomer.

[0110] The specific viscosity is measured using a high temperature Agilent (or Viscotek Corporation) viscometer, which has four capillaries arranged in a Wheatstone bridge configuration and two pressure sensors. One sensor measures the total pressure drop across the detector, and the other sensor, located between the two sides of the bridge, measures the pressure difference. The specific viscosity η of the solution flowing through the viscometer is s The intrinsic viscosity η at each point in the chromatogram is calculated from their output. s From the equation [η] = η s / c is calculated, where c is the concentration and is measured from the IR5 broadband channel output. The viscosity MW at each point is calculated as M = K PS M αps+1 / [η], where α ps is 0.67, K ps It is 0.000175.

[0111] The branching index (g') was calculated using the output of the GPC-IR5-LS-VIS method as follows: vis ). Average intrinsic viscosity of the sample [η] avgCalculated by the following formula: wherein the sum is taken from all chromatogram slices i between the integration limits. Branching index g' vis Defined as Among them, M v is the viscosity average molecular weight based on the molecular weight determined by LS analysis, and K and α are the K and α of the benchmark linear polymer, which for the purposes of this invention are: for linear ethylene polymers, α = 0.695 and K = 0.000579, for linear propylene polymers, α = 0.705 and K = 0.0002288, for linear butene polymers, α = 0.695 and K = 0.000181, and for ethylene-butene copolymers, α = 0.695 and K is 0.000579 × (1 - 0.0087 w2b + 0.000018 × (w2b) 2 ), where w2b is the gross weight percentage of the butene comonomer. For ethylene-hexene copolymers, α is 0.695 and K is 0.000579×(1-0.0075×w2b), where w2b is the gross weight percentage of the hexene comonomer. For ethylene-octene copolymers, α is 0.695 and K is 0.000579×(1-0.0077×w2b), where w2b is the gross weight percentage of the octene comonomer. Unless otherwise stated, concentrations are expressed in g / cm 3 The molecular weight is expressed in g / mole and the intrinsic viscosity (and hence K in the Mark-Houwink equation) is expressed in dL / g. The w2b value is calculated as discussed above.

[0112] Melt index (MI, also known as I2) is measured according to ASTM D1238 at 190°C under a load of 2.16 kg, unless otherwise specified. The unit of MI is g / 10min or dg / min. High load melt index (HLMI, also known as I 21 ) is the melt flow rate measured at 190° C. under a load of 21.6 kg according to ASTM D-1238. The unit of HLMI is g / 10 min or dg / min.

[0113] Melt Index Ratio (MIR) is the ratio of the high load melt index to the melt index, or I 21 / I2.

[0114] Density was measured by passing the sample through a density gradient column as described in ASTM D1505 after it had been slowly cooled to room temperature (i.e., over 10 minutes or more) and aged for a time sufficient to maintain a constant density of + / - 0.001 g / cm 3 The unit of density is g / cm 3 .

[0115] The composition distribution breadth index (CDBI) is measured by the procedure described in PCT Publication WO 93 / 03093 published February 18, 1993 (particularly columns 7 and 8), and Wild et al., J. Poly. Sci., Poly. Phys. Ed., Vol. 20, p. 441 (1982) and US 5,008,204, including disregarding fractions having a weight average molecular weight (Mw) of less than 15,000 when determining the CDBI.

[0116] The width of the composition distribution of a polymer can also be determined by T 75 -T 25 Characterization. This is readily determined using well-known techniques for separating the individual fractions of a copolymer sample. One such technique is temperature rising elution fractionation (TREF), as described in Wild et al., J. Poly. Sci., Poly. Phys. Ed., vol. 20, pg. 441 (1982) and in U.S. Pat. No. 5,008,204. For example, TREF can be measured using an analytical size TREF instrument (Polymerchar, Spain) having a column with the following dimensions: internal diameter (ID) 7.8 mm, external diameter (OD) 9.53 mm, and column length 150 mm. The column can be packed with steel beads. 0.5 mL of a 4 mg / mL polymer solution in o-dichlorobenzene (ODCB) containing 2 g BHT / 4 L is fed to the column and cooled from 140° C. to −15° C. at a constant cooling rate of 1.0° C. / min. Subsequently, ODCB can be pumped through the column at a flow rate of 1.0 ml / min and the column temperature can be increased at a heating rate of 2°C / min to elute the polymer. -1 The concentration of the polymer in the eluted liquid is determined by the absorbance at a wave number of . The concentration of the ethylene-α-olefin copolymer in the eluted liquid can be calculated from the absorbance and plotted as a function of temperature. The T used herein is 75 -T 25 The value is where T 25 is the temperature in degrees Celsius at which 25% of the eluted polymer is obtained via TREF analysis, T 75 is the temperature in degrees Celsius at which 75% of the eluted polymer is obtained.

[0117] Dynamic shear melt rheology data were measured using parallel plates (diameter = 25 mm) with an Advanced Rheometrics Expansion System (ARES) in dynamic mode under a nitrogen atmosphere. For all experiments, the rheometer was thermally stabilized at 190°C for at least 30 minutes before the compression molded samples of the resin were inserted onto the parallel plates. In order to determine the viscoelastic behavior of the samples, frequency sweeps in the range of 0.01 to 385 Rad / s were performed at a temperature of 190°C under constant strain. Depending on the molecular weight and temperature, strains of 10% and 15% were used and the linearity of the response was confirmed. A stream of nitrogen was circulated through the sample oven to minimize chain extension or crosslinking during the experiment. All samples were compression molded at 190°C and no stabilizer was added. If the strain amplitude is small enough to make the material behavior linear, a sinusoidal shear strain is applied to the material. It can be shown that the resulting steady-state stress will also oscillate sinusoidally at the same frequency, but will be displaced by a phase angle δ relative to the strain wave. The stress leads the strain δ. For purely elastic materials, δ = 0° (stress and strain are in phase), and for purely viscous materials, δ = 90° (stress leads strain by 90°, although stress and strain rate are in phase). For viscoelastic materials, 0 < δ < 90. The shear thinning slope (STS) is measured using a plot of the logarithm (base 10) of the dynamic viscosity against the logarithm (base 10) of the frequency. The slope is 100s -1 log(dynamic viscosity) at a frequency of 0.01s -1 The difference in log(dynamic viscosity) at the frequency of the product is divided by 4. Dynamic viscosity is also called complex viscosity or dynamic shear viscosity. The dynamic shear viscosity (η*) versus frequency (ω) curve is fitted using the Cross model (see, e.g., CW Macosco, Rheology: Principles, Measurements, and Applications, Wiley-VCH, 1994):

[0118] The three parameters in this model are: η0, zero shear viscosity; λ, average relaxation time; and n, power law exponent. When dynamic viscosity is independent of frequency, zero shear viscosity is the value at the plateau in the Newtonian region of the flow curve at low frequencies. The average relaxation time corresponds to the inverse of the frequency at which shear thinning begins. The power law exponent describes the degree of shear thinning because the slope of the flow curve at high frequencies on a log(η*)-log(ω) plot is on the order of 1-n. For Newtonian fluids, n=1, and the dynamic complex viscosity is independent of frequency. For the polymers of interest here, n<1, so enhanced shear thinning behavior is represented by a decrease in n (an increase in 1-n).

[0119] Extensional rheology was performed at 150°C using a Sentmanat Extensional Rheometer-2 (SER-2) mounted in a rotational rheometer MCR 501 (Anton-Paar). The SER-2 consists of two counter-rotating drums on which the film sample is mounted at 150°C and fixed with a latch. One of the drums is connected to the rheometer torque sensor and a rotation motor, which imposes a purely uniaxial extensional deformation on the sample. The values ​​of the applied strain rate and the measured torque are used to calculate the extensional viscosity. The film specimens were prepared by compression molding at 200°C. The typical dimensions of the specimens were 12.7 mm × 12.7 mm × 0.5 mm. In addition, the linear viscoelastic (LVE) envelope was obtained by starting a steady shear experiment using a cone and plate fixture, and using the Trouton rule in extensional transient mode, h = 3h, where h7 is the extensional viscosity and h is the shear viscosity.

[0120] SHR or strain hardening ratio is defined as: where η E，Peak is the peak extensional viscosity in the strain hardening region; η E，Peak is the extensional viscosity linear viscoelastic region.

[0121] The melt strength of the modified polyethylene at 190°C was measured using a Gottfert Rheotens melt strength apparatus. To determine the melt strength, the modified polyethylene melt strand extruded from a capillary die was clamped between two counter-rotating wheels on the apparatus. 2 The take-up speed is increased by constant acceleration. The maximum tensile force (in cN) reached before the filament breaks or starts to show tensile resonance is measured as the melt strength. The draw-down ratio is defined as the ratio between the take-up speed at maximum tension and the extrusion rate at the die outlet. The temperature of the rheometer is set at 190°C. The capillary die has a length of 30 mm and a diameter of 2 mm. The modified polyethylene melt is extruded from the die at a speed of 18 mm / sec. The distance between the die outlet and the contact point of the wheel should be 122 mm.

[0122] When appropriate, the following film properties and descriptions are intended to encompass measurements taken in both the machine and transverse directions. These measurements are reported separately, with the designation "MD" indicating measurements taken in the machine direction and "TD" indicating measurements taken in the transverse direction.

[0123] Thickness was measured using a Measuretech Series 200 instrument and reported in mils. This instrument uses a capacitance gauge to measure film thickness. For each film sample, ten film thickness data points were measured per inch of film in the transverse direction as the film passed through the capacitance gauge. From these measurements per inch of film, an average thickness measurement was determined and reported.

[0124] Elmendorf Tear is measured as specified in ASTM D-1922 and is reported in grams (g) or grams per mil (g / mil).

[0125] Tensile strength at yield was measured as specified in ASTM D-882 and reported in pounds per square inch (lb / in 2 or psi) reported.

[0126] Tensile strength at break was measured as specified in ASTM D-882 in pounds per square inch (lb / in 2 or psi) reported.

[0127] Elongation at yield was measured as specified in ASTM D-882 and reported as percent (%).

[0128] Elongation at break was measured as specified in ASTM D-882 and reported as percent (%).

[0129] 1% secant modulus (M) is measured as specified in ASTM D-882 and is expressed in pounds per square inch (lb / in 2 or psi) reported.

[0130] Haze was measured as specified in ASTM D-1003 and reported as a percentage (%).

[0131] Clarity was measured as specified in ASTM D-1746 and reported as a percentage (%).

[0132] Unless otherwise stated, dart drop F was measured as specified in ASTM D-1709, Method A. 50 , or Dart Impact or Dart Impact Strength (DIS), reported in grams (g) and / or grams per mil (g / mil).

[0133] "Puncture Force / Energy" - Probe penetration energy testing is accomplished using an Instron universal tester that records continuous readings of the force (stress) and penetration (strain) curves. A 6 inch x 6 inch (15 cm x 15 cm) film specimen is securely mounted in a compression load cell to expose a 4 inch (10 cm) diameter test area. Two HDPE slides, each 2 inches x 2 inches (5 cm x 5 cm) and each approximately 0.25 mil (6.35 μm) thick, are placed loosely on the test surface. A 3 / 4 inch (1.875 cm) diameter, slender, matte-finished stainless steel probe, moving at a constant speed of 10 inches / minute (25 cm / min), is lowered into the film and the stress / strain curve is recorded and plotted. "Puncture Force" is the maximum force (pounds) encountered or pounds / mil (lb / mil) encountered. The area under the stress / strain curve is machine integrated, which represents the energy expended to cause the test failure of the film during penetration and is reported as "puncture energy" (inch pounds) and / or inch-pounds / mil (in-lb / mil). The probe penetration distance is not recorded in these tests unless otherwise specified.

[0134] Where any of the above properties are reported in pounds per square inch, grams per mil, or any other dimension reported per unit area or per unit thickness, the ASTM method cited for each property is followed, except that film thickness is measured according to ASTM D-374, Method C. Example

[0135] It should be understood that although the embodiments have been described in conjunction with their specific embodiments, the foregoing description is intended to illustrate rather than limit the scope of the present disclosure. Other aspects, advantages and improvements will be apparent to those skilled in the art to which the present disclosure pertains.

[0136] The ethylene-propylene-vinylidene norbornene terpolymer "A" used as a modifier in the examples was prepared according to U.S. Patent No. 7,511,106 and had 79 wt% ethylene-derived units based on the weight of the terpolymer, 0.96 wt% VNB based on the weight of the terpolymer, with the remainder being propylene-derived units. It had a carbonyl group of 0.885 g / cm 3 The density and characteristic long chain branching (at G*=10 5 The terpolymer had a loss angle (δ) of 30.3 at 0.245 Rad / s, a tan (δ) @ 0.245 Rad / s of 0.731, an STR of 110, and a Mooney viscosity of 25 MU (1+4, 125°C). The terpolymer was also mixed with 0.16 wt% of Irganox TM 1076 Antioxidant Blend.

[0137] In the comparative samples C-1 to C-5 and the inventive samples I-1 to I-10, the base resin BF is Exceed TM Polyethylenes 1012HA, 2018HA, 3518CB, 4518PA, and 7518CB, Performance PE available from ExxonMobil Chemical Company (Houston, Texas). To prepare inventive samples I-1 to I-6, pellets of the base resin and terpolymer modifier "A" were pre-mixed in the solid state and extruded on a 57 mm Werner & Pfleiderer twin-screw extruder (i.e., ZSK-57). Examples I-7 to I-10 were prepared using a 1" Haake twin-screw extruder with a L / D of 15 followed by a strand pelletizer. Some properties and processing conditions of the sample blends are reported in Table 1 below. In addition, an antioxidant package was added to all compounded compositions. The antioxidant consisted of 0.05 wt% Irganox TM 1076 and 0.1 wt% Irgafos TM 168 (available from BASF). Extruder temperature settings were 180 / 185 / 190 / 195°C. Concentrations are weight percentages of the final blend. Some properties and processing conditions Table 1

[0138] Comparative samples C-1 to C3 and inventive samples I-1 to I-6 were tested for film applications. All blown films were produced on a Hosokawa Alpine blown film line. Some general process parameters are shown in Table 2. The line was equipped with a 160 mm single-layer die connected to a 90 mm and 30 L / D single screw extruder. Films were produced using a 60 mil die gap and a 2.5 blow-up ratio. The target film thickness was 1.0 mil (25.4 microns). The extruder profile followed a setting of 330 / 330 / 350 / 350 / 350 / 350 / 350°F. The die zone was set to 380 / 380 / 380 / 380°F. Table 2

[0139] By blending 1-3 wt% of Modifier A, the inventive samples showed a significant increase in melt strength, a strain hardening ratio exceeding 1.5, and an increase in relaxation time relative to their respective comparative examples.

[0140] In comparative samples C-6 to C-7 and inventive samples I-11 to I-14 (see Table 3 below), base resins G and H were prepared using a bis(n-propylcyclopentadienyl)hafnium dichloride / MAO catalyst system in a gas phase reactor. The density of resin G was 0.916 g / cm 3 , MI is 0.7g / 10min, and I 21 The ratio of / I2 is 28. Resin H has a density of 0.918 g / cm3, an MI of 1.0 g / 10 min and an I 21 / I2 ratio. In particular, G and H used in the following examples were prepared essentially as described in the examples described in U.S. Patent No. 6,956,088 B2, the entirety of which is incorporated herein by reference. Process conditions were manipulated as needed to obtain resins having the resulting density and melt index. To prepare inventive samples I-11 to I-14, pellets of base resin and "A" were premixed in the solid state and extruded on a 57 mm Werner & Pfleiderer twin screw extruder (i.e., ZSK-57). An antioxidant package was added to all compounded compositions. The antioxidant consisted of 0.05 wt% of Irganox TM 1076 and 0.1 wt% Irganox TM The composition was 168 (available from BASF). The extruder temperature was set at 180 / 185 / 190 / 195° C. Concentrations are weight percent of the final blend. Table 3

[0141] Film applications of comparative samples C-6 and C-7 and samples I-11 to I-14 of the present invention were tested (see Table 4 below). All blown films were produced on a Hosokawa Alpine blown film production line. Some general process parameters are shown in Table 4. The production line was equipped with a 160 mm single-layer die connected to a 90 mm and 30 L / D single screw extruder. Films were produced using a 60 mil die gap and a 2.5 blow-up ratio. The target film thickness was 1.0 mil (25.4 microns). The extruder profile was set at 330 / 330 / 350 / 350 / 350 / 350 / 350°F. The die zone was set at 380 / 380 / 380 / 380°F. Table 4

[0142] In comparative samples C-8 and C-9 and inventive samples I-15 and I-16 (see Table 5 below), base resin BF is ExxonMobil ® commercially available from ExxonMobil Chemical Company (Houston, Texas). TMLLDPELL1001.32 and LL1002KW. To prepare inventive samples I-15 to I-16, pellets of base resin and "A" were premixed in the solid state and extruded on a 57 mm Werner & Pfleiderer twin screw extruder (i.e., ZSK-57). An antioxidant package was added to all compounded compositions. The antioxidant consisted of 0.05 wt% Irganox TM 1076 and 0.1 wt% Irganox TM The composition was 168 (available from BASF). The extruder temperature was set at 180 / 185 / 190 / 195° C. Concentrations are weight percent of the final blend. Table 5

[0143] Film applications of comparative samples C-8 and C-9 and inventive samples I-15 and I-16 were tested (see Table 6 below). All blown films were produced on a Hosokawa Alpine blown film production line. Some general process parameters are shown in Table 6. The production line was equipped with a 160 mm single-layer die connected to a 90 mm and 30 L / D single screw extruder. Films were produced using a 60 mil die gap and a 2.5 blow-up ratio. The target film thickness was 1.0 mil (25.4 microns). The extruder profile was set at 330 / 330 / 350 / 350 / 350 / 350 / 350°F. The die zone was set at 380 / 380 / 380 / 380°F. Table 6

[0144] In general, the modified polyethylene and films of the present disclosure can have, for example, high melt strength and maintained or improved melt viscosity and other film physical properties. Dart drop and MD tear properties are significantly reduced to some extent, but only by about 10% and 20%, respectively, while haze and processability are significantly improved (haze is significantly reduced by 50%). Compared with conventional compositions and methods, these attributes provide improved bubble stability and provide a significant increase in film output while maintaining the same or similar pressure. Increased melt strength (e.g., tensile strain hardening) allows the bubble to balance its own weight before solidification, thereby contributing to improved bubble stability, film thickness uniformity and the ability to blow out large bubbles (e.g., geomembranes). Therefore, the blends of the present invention are very suitable for target applications in films with excellent performance balance, particularly in applications where minimum haze is of key importance, while the blends of the present invention are significantly easier to process, so the economic efficiency is also greatly improved for film manufacturers.

[0145] Unless otherwise specified, the phrase "consisting essentially of" does not exclude the presence of other steps, elements, or materials (whether or not specifically mentioned in the specification) so long as these do not affect the basic and novel characteristics of the disclosure, and further, they do not exclude impurities and variations normally associated with the elements and materials used.

[0146] For simplicity, only certain numerical ranges are explicitly disclosed herein. However, a lower limit can be combined with any other upper limit to define an unspecified range. Similarly, a lower limit can be combined with any other lower limit to define an unspecified range. Similarly, an upper limit can be combined with any upper limit to define an unspecified range. In addition, even if not explicitly stated, each point or individual value between the two endpoints is included in the range. Therefore, each point or individual value can itself be used as a lower limit or upper limit in combination with other points or individual values ​​or other lower or upper limits to define an unspecified range.

[0147] All prior art documents are incorporated herein by reference to the extent that their disclosures are not inconsistent with the description of the present disclosure. In addition, all documents and references cited herein (including test procedures, publications, patents, journal articles, etc.) are incorporated herein by reference in their entirety to the extent that their disclosures are not inconsistent with the description of the present disclosure.

[0148] While this disclosure has been described in terms of numerous embodiments and examples, those skilled in the art, after reading this disclosure, will appreciate that other embodiments can be devised without departing from the scope and spirit of this disclosure.

Claims

1. A modified polyethylene comprising the product of a combination of: a) 95-99.9 wt% of a metallocene-catalyzed polyethylene comprising 85-99.9 wt% of units derived from ethylene and units derived from C3 to C 10 α-olefin units, the polyethylene has 0.900 to 0.940 g / cm 3 density; and b) 0.10-5 wt% of an elastomer-containing modifier having long chain branching and further having at least 60 wt% of units derived from ethylene, 0-10 wt% of units derived from cyclic diene monomers; and the balance derived from one or more C3-C 10 Units of α-olefins, wherein the elastomer has a Mooney viscosity of 10 to 40 MU (ML, 1+4@100° C.).

2. The modified polyethylene of claim 1 , wherein the metallocene-catalyzed polyethylene is selected from one or more of the following: (i) a narrow-CD mLLDPE having a CDBI of at least 60% and a molecular weight distribution (MWD, defined as Mw / Mn) of 1.5 to 4; (ii) a long-chain branched mLLDPE having a CDBI greater than or equal to 70% and a melt index ratio (MIR) of 20 to 40; (iii) a narrow MWD BOCD-mLLDPE having an MWD of 2.0 to 4.5, a CDBI of less than 40%, and a broad orthogonal composition distribution; and (iv) a broad-BOCD-mLLDPE having an MWD of 6 to 10, a CDBI of less than 40%, and a broad orthogonal composition distribution.

3. The modified polyethylene of claim 2, wherein said polyethylene is said narrow-CD mLLDPE, and further has one or more of the following properties: a) CDBI of 60% to 80%; b) a melt index (I) of 0.1 to 5 g / 10 min 2.16 ), c) a weight average molecular weight (Mw) of 45,000 to 120,000 g / mol; d) a number average molecular weight (Mn) of 20,000 to 55,000 g / mol; and e) 0.905 to 0.940 g / cm 3 density.

4. The modified polyethylene of claim 2, wherein the polyethylene is the long chain branched mLLDPE, and further has one or more of the following properties: a) MIR of 25 to 35; b) a shear thinning ratio (STR) of less than 15; c) an inflection point in a van Gurp-Palmen plot of phase angle vs. complex modulus (Pa) of the polyethylene; and d) a high load melt index (HLMI) of 10 to 75 g / 10 min.

5. The modified polyethylene of claim 2, wherein said polyethylene is said narrow MWD BOCD-mLLDPE, and further has one or more of the following properties: a) an Mw of 20,000 to 200,000 g / mol; b) Mz / Mw greater than 1.5; c) T of 5 to 10 75 -T 25 ; d) CDBI less than 35%; e) Melt index (I) 0.1-5 g / 10 min 2.16 ),and f)MIR of 20-35.

6. The modified polyethylene of claim 2, wherein said polyethylene is said broad BOCD-mLLDPE, and further has one or more of the following properties: a)MWD of 6.4 to 9.5; b) T of 15°C or greater 75 -T 25 ;and c) CDBI less than 35%.

7. The modified polyethylene of claim 1 or any one of claims 2 to 6, wherein the C3 to C 10 The α-olefin units are selected from 1-butene, 1-hexene and 1-octene.

8. The modified polyethylene of claim 1 or any one of claims 2 to 7, wherein the modifier has one or more of the following properties: a) Mooney relaxation area (MLRA) between 100 and 500 MU-sec; b) Complex modulus G*=1.1×10 5 Phase angle (δ) under Pa; c) tan(δ) at 0.245 Rad / s of 0.500 to 0.800; and d) Shear Thinning Ratio (STR) of 50 to 300.

9. The modified polyethylene of claim 8, wherein the modifier has one or more of the following properties: a) Complex modulus G* = 1.1 × 10 5 Phase angle (δ) under Pa; b) tan(δ) at 0.245 Rad / s of 0.550 to 0.800; and c) STR of 75 to 250.

10. The modified polyethylene of claim 8 or claim 9, wherein the cyclic-diene monomer is selected from the group consisting of dicyclopentadiene (DCPD), norbornadiene (NBD), 5-vinyl-2-norbornene (VNB), ethylidene norbornene (ENB), derivatives thereof, and combinations thereof.

11. The modified polyethylene of claim 10, wherein the cyclic-diene monomer is 5-vinyl-2-norbornene (VNB).

12. The modified polyethylene of any one of the preceding claims, wherein the modified polyethylene comprises 0.50 to 5.0 wt% of the modifier.

13. A film comprising the modified polyethylene according to any one of the preceding claims.

14. The film of claim 13, wherein the film is produced by a blown film extrusion process, the film having a measured haze that is at least 50% lower than a film produced by the same blown film extrusion process using the polyethylene component of the modified polyethylene in place of the modified polyethylene.

15. The film of claim 13 or claim 14, wherein the film is produced by a blown film extrusion process and has one or more of the following properties: (a) a strain hardening ratio that is at least 1% greater than a film produced by an identical blown film extrusion process using the polyethylene component of the modified polyethylene in place of the modified polyethylene; (b) a puncture force of at least 90% of the value measured for a film produced by the same blown film extrusion process using the polyethylene component of the modified polyethylene in place of the modified polyethylene; (c) a puncture burst energy of at least 90% of the value measured for a film produced by the same blown film extrusion process using the polyethylene component of the modified polyethylene in place of the modified polyethylene; (d) a TD 1% secant modulus that is at least 1% higher than a film produced by the same blown film extrusion process using the polyethylene component of the modified polyethylene in place of the modified polyethylene; (e) an MD 1% secant modulus that is at least 1% higher than a film produced by the same blown film extrusion process using the polyethylene component of the modified polyethylene in place of the modified polyethylene; (f) an MD tear at least 1% higher than a film produced by the same blown film extrusion process using the polyethylene component of the modified polyethylene in place of the modified polyethylene; (g) Dart impact of at least 90% of the value measured for a film produced by the same blown film extrusion process using the polyethylene component of the modified polyethylene in place of the modified polyethylene.

16. The film of claim 15 having all of properties (a) to (g).

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