Ethylene copolymer compositions and articles made therefrom

Abstract

Provided herein are ethylene copolymers having at least two TREF peaks made from a single catalyst and methods of making the same. The ethylene copolymer has at least 60% by weight of ethylene derived units and 10 to 40% by weight of comonomer derived units from one or more C4 to C20 alpha-olefins. The ethylene copolymer also has a density in the range of from 0.850 g / cc to 0.915 g / cc; an MI in the range of from 0.1 dg / min to 1000 dg / min; and an MIR (I21.6 / I2.16) in the range of 18 to 100 wherein the at least one TREF peak is a primary fraction comprising at least 90% by weight of the copolymer and the at least one TREF peak is a secondary fraction comprising less than 8% by weight of the copolymer and occurring in the range of 60 DEG C to 95 DEG C. The ethylene copolymers have excellent pellet stability, where minimal or no anti-blocking agent is required, and can be used in blown film, elastic, and automotive TPO applications.

Description

[0001] Cross-reference to related applications

[0002] This application claims the benefit of U.S. Provisional Application 63 / 518,006, filed August 7, 2023, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] Embodiments of the present invention generally relate to ethylene copolymers with different TREF peaks. Embodiments of the present invention also relate to blown films and TPO articles made from ethylene copolymers with different TREF peaks. Background Technology

[0004] Ethylene-based copolymers are in high demand due to their high elasticity, flexibility, toughness, transparency, and processability. Such elastomers have a wide range of applications, including thermoplastic polyolefins (TPO), blown and cast films, injection molded containers and other articles, nonwovens, and hot melt adhesives. Both high-viscosity and low-viscosity ethylene-based copolymers have been produced. Unfortunately, conventional ethylene-based copolymers fail to achieve a good balance of elasticity, stiffness, and flow properties. As a result, consumers of such ethylene-based copolymers often combine multiple granular forms of ethylene-based elastomer products in their production facilities to achieve the desired elasticity, stiffness, and flowability required for certain end-use products such as automotive TPO, packaging films, and other polymer modifications. The processing costs of combining so many products can be high due to the need for multiple conveyor systems.

[0005] Furthermore, the mixing of different ethylene-based elastomer products can lead to pellet agglomeration and consequently flow problems in production equipment. Amorphous or low-crystallinity polyolefin copolymers, such as plastomers, are also prone to agglomeration (clumping, linking, bridging) during pellet drying-transfer-bagging steps in the manufacturing process, during transportation, or during storage in a warehouse. It is well known in the manufacturing industry that producing stable pellets of low-density resins (<0.870 g / cc) is a challenge due to the adhesion / stickiness between pellets stored under normal environmental conditions. This situation is exacerbated if the low-density resin is also a high-flow-rate material, i.e., >5 MI.

[0006] Numerous attempts have been made to improve shelf life and pellet stability in low-density semi-crystalline or amorphous polymers. Resin manufacturers typically treat pellet surfaces with a partitioning agent along with a dusting agent. Common methods include coating pellets with anti-sticking agents such as CaSt2 or siloxanes, or treating physical surface interactions by dusting with talc or polyethylene powder. For example, WO 2020 / 006396 A1, US 6852 787B1, US 5366645 (Vacuum-phase SiO2), and US 10,544,295 B2 (HMA with a covering film) disclose coating methods using calcium stearate, polydimethylsiloxane, talc, or polyethylene powder. However, these methods require additional equipment such as spray systems, pellet water tanks, or dust conveying and handling systems.

[0007] Other attempts to reduce agglomeration and improve pellet stability have tested various catalyst systems to produce less viscous, multi-peaked resins. For example, US 10,023,669 B2 (LG Chem) discloses an ethylene-octene composition with three TREF peaks produced using a mixture of two catalysts. US 10,961,335 B2 discloses an ethylene-butene composition with three CFC peaks produced using a mixture of two metallocene catalysts. Other methods, such as those disclosed in US 9,688,795 B2 and US 2019 / 0194503 A1, have tested improved pellet flowability in low-density, low-viscosity ethylene-olefin copolymers and correlated them with high comonomer content (by weight %) from crystallization elution fractionation techniques.

[0008] Other references of interest include: US20200010657, US11155658 B2, US10774205B2, US8569434 B2 and US 6,369,176 B1. Summary of the Invention

[0009] In one embodiment, this document provides an ethylene copolymer (“ECP”) having at least two TREF peaks prepared from a single metallocene catalyst. The ethylene copolymer may have at least 60 wt% ethylene-derived units and 10-40 wt% comonomer-derived units from one or more C4-C20 α-olefins, wherein the copolymer has a density in the range of 0.850 g / cc to 0.915 g / cc; an MI in the range of 0.1 dg / min to 1000 dg / min; and a MIR (I21.6 / I2.16) in the range of 18 to 100. At least one TREF peak is a major fraction comprising at least 90 wt% of the copolymer, and at least one other TREF peak is a minor fraction comprising less than 8 wt% of the copolymer and occurring in the range of 60°C to 95°C.

[0010] This document also provides a method for preparing an ethylene copolymer having at least two TREF peaks, said ethylene copolymer being produced by solution polymerization using a single metallocene catalyst. In one embodiment, the method includes feeding ethylene, at least one comonomer, and a solvent in controlled proportions into a conduit upstream of a solution polymerization reactor; adding a single metallocene catalyst and an activator into the conduit; polymerizing at least a portion of the ethylene and at least one other monomer in the solution polymerization reactor to produce an ethylene prepolymer having at least 5% by weight of the comonomer; feeding the ethylene prepolymer into the solution polymerization reactor; feeding additional ethylene, comonomer, catalyst, and activator in controlled proportions and optionally additional solvent into the solution polymerization reactor; and operating the solution polymerization reactor to produce an ethylene copolymer wherein at least one TREF peak is a major fraction comprising at least 90% by weight of the ethylene copolymer, and wherein at least one other TREF peak is a minor fraction comprising less than 8% by weight of the ethylene copolymer and occurring in the range of 60°C to 95°C.

[0011] In another embodiment, the method includes feeding ethylene, at least one comonomer, and a solvent into a solution polymerization reactor in a controlled proportion; adding a single metallocene catalyst and an activator into the solution polymerization reactor; polymerizing at least a portion of the ethylene and at least one other monomer in the solution polymerization reactor to produce an ethylene copolymer having at least 5% by weight of the comonomer; discharging the ethylene prepolymer from the solution polymerization reactor; and feeding additional ethylene into a downstream conduit of the solution polymerization reactor in a controlled proportion to provide an ethylene copolymer product, wherein at least one TREF peak is a major fraction comprising at least 90% by weight of the ethylene copolymer product, and wherein at least one other TREF peak is a minor fraction comprising less than 8% by weight of the ethylene copolymer product and occurring in the range of 60°C to 95°C.

[0012] These and other features and attributes of this disclosure, and their advantageous applications and / or uses, will become apparent from the following detailed description. Attached Figure Description

[0013] To assist those skilled in the art in preparing and using the subject matter of this article, please refer to the accompanying drawings, as briefly described below.

[0014] Figure 1 TREF composition curves showing illustrative low-density copolymers prepared according to one or more embodiments described herein, compared with commercially available copolymers, namely C3, C1 and C4, having similar densities and MI.

[0015] Figure 2 shows TREF composition curves of illustrative medium-density copolymers prepared according to one or more embodiments described herein, compared with commercially available copolymers having similar densities and MI, namely a.) C5, C7 and S31, b.) C6, C8 and S22.

[0016] Figure 3 TREF composition curves showing illustrative high-density copolymers prepared according to one or more embodiments described herein, compared with commercially available copolymers, namely C9 and C10, having similar density and MI.

[0017] Figure 4 The TREF elution temperature peaks (peak 1 and peak 2) for various ethylene copolymers prepared according to one or more embodiments described herein as a function of ethylene weight % are shown.

[0018] Figure 5 The HD fraction (wt%) of the total composition of various ethylene copolymers prepared according to one or more embodiments described herein as a function of total ethylene content (wt%) is shown.

[0019] Figure 6 A schematic diagram showing an illustrative solution polymerization method suitable for preparing ethylene copolymers according to one or more embodiments described herein.

[0020] Figure 7 This shows the weight percentage of the high-density TREF fraction of the ethylene copolymer provided in the examples, relative to the catalyst feed rate into the reactor relative to the activator, according to one or more embodiments described herein.

[0021] Figure 8 Another schematic diagram illustrating an illustrative solution polymerization method suitable for preparing ethylene copolymers according to one or more embodiments described herein. Detailed Implementation

[0022] It should be understood that the following disclosure describes several exemplary embodiments for implementing different features, structures, and / or functions of the present invention. The exemplary embodiments of components, arrangements, and configurations described below are intended to simplify this disclosure; however, these exemplary embodiments are provided as examples only and are not intended to limit the scope of the invention. Additionally, reference numerals and / or letters may be repeated in various exemplary embodiments and in the accompanying drawings provided herein. Such repetition is for simplicity and clarity and does not, in itself, define the relationship between the various exemplary embodiments and / or configurations discussed in the drawings. Furthermore, the exemplary embodiments presented below can be combined in any way without departing from the scope of this disclosure; that is, any element from one exemplary embodiment can be used in any other exemplary embodiment.

[0023] Ethylene copolymers, their preparation systems, and methods are provided. In one aspect, this paper provides the production of copolymers with two distinct density peaks using a single catalyst and a single reactor. Ethylene copolymers with a density greater than 0.020 g / cc are used in blown film, elastic, and automotive TPO applications. These ethylene copolymers typically have a higher density component of 0.1% to 10% by weight, which does not significantly alter the physical properties of the composition or its end-use application, but significantly improves its pellet stability and shelf life. Such secondary fractions with higher densities (0.1% to 10% by weight) may also have high or low molecular weight index (MI). In some embodiments, the density range of the secondary fraction may be from about 0.865 g / cc to about 0.925 g / cc, and the density range of the primary fraction may be from about 0.850 g / cc to about 0.915 g / cc, provided that the density of the secondary fraction is at least 0.020 g / cc, at least 0.025 g / cc, at least 0.030 g / cc, at least 0.035 g / cc, or at least 0.040 g / cc greater than the density of the primary fraction.

[0024] This secondary HD fraction, together with the primary LD fraction, significantly improves the performance properties of elastomers used in membrane, elastic, and TPO applications without significantly altering the overall product density, physical properties, and flow characteristics. This combination of high and low densities of any desired molecular weight of the secondary component can be achieved in a single reactor loop via a catalyst / monomer inlet without additional installation costs.

[0025] The method uses a single catalyst to prepare ethylene copolymers having at least two TREF peaks in a single reactor. “TREF” refers to the temperature rise elution fractionation (TREF) technique described in Wild et al., J. Poly. Sci., Poly. Phys. Ed., Vol. 20, p. 441 (1982) and U.S. Patent No. 5,008,204, which is incorporated herein by reference. In some embodiments, the ethylene copolymer has at least two TREF peaks. At least one of those TREF peaks is a major fraction comprising at least 90%, 92%, or 95% by weight of the copolymer, and at least one other TREF peak is a minor fraction comprising less than 8%, less than 6%, less than 5%, or less than 3% by weight of the copolymer and occurring in the range of 60°C to 95°C. In some embodiments, the major fraction TREF peak occurs in the range of 0°C to 80°C. In some other embodiments, the major fraction TREF peak may range from 60 to 75°C, or 70 to 85°C, or 80 to 95°C.

[0026] Ethylene copolymers can be produced in a single reactor without the need for additional reactors and using a single catalyst without the need for additional catalysts. The resulting ethylene copolymers exhibit excellent pellet stability with minimal or no anti-blocking agents added. For example, the resulting ethylene copolymers do not require any added pellet coating additives, such as metal stearates, siloxanes, or talc separators, but any such additives may be used to improve pellet stability and / or tackiness. Similarly, the resulting ethylene copolymers do not require any added HDPE or LDPE.

[0027] The presence of high-density fractions does not affect the performance of the ethylene copolymer and requires no additional capital investment in the process. Therefore, cost savings are significant. Firstly, capital costs are significantly reduced because only a single reactor and a single catalyst are required, and secondly, the cost of the additives produced is significantly reduced.

[0028] Surprisingly and unexpectedly, the molecular weight and density of the ethylene copolymer (if properly controlled) provide pellet stability by forming an encapsulation structure with high-density (HD) fractions and low-molecular-weight chains surrounding its outer surface, thus providing a core-shell structure. Because of the low-molecular-weight, high-density fractions migrating to the membrane surface, such pellets can provide a reduced coefficient of friction for the membrane. Ethylene copolymers are particularly suitable for all molding, elastic, and membrane applications.

[0029] Certain embodiments and features have been described using a set of upper limits and a set of lower limits. It should be understood that, unless otherwise stated, the scope encompasses a range including any combination of two values, such as any lower limit value combined with any upper limit value, any combination of two lower limits, and / or any combination of two upper limits. Certain lower limits, upper limits, and ranges appear in one or more of the following claims. All numerical values ​​are those indicated by “about” or “approximately” and take into account experimental errors and biases expected by those skilled in the art.

[0030] Furthermore, certain terms are used throughout the following description and claims to refer to specific components. As those skilled in the art will appreciate, various entities may refer to the same component by different names, and thus, the naming conventions used for the elements described herein are not intended to limit the scope of the invention, as specifically defined herein. Moreover, the naming conventions used herein are not intended to distinguish between components with different names but the same function.

[0031] In the following discussion and in the claims, the terms “comprising” and “including” are used in an open-ended manner and should therefore be construed as meaning “including, but not limited to”. The phrase “consisting substantially of” means that the described / claimed composition does not include any other component that would substantially alter its properties by more than 5% of such properties, and in no case does not include any other component at a level greater than 3% by mass.

[0032] The term “or” is intended to include both exclusive and inclusive cases, meaning that “A or B” is intended to be synonymous with “at least one of A and B”, unless otherwise expressly stated herein.

[0033] Unless the context clearly specifies otherwise, the indefinite articles “a” and “an” refer to both the singular (i.e., “a”) and plural (i.e., one or more) forms. For example, unless specified to the contrary or the context clearly indicates that only one olefin is used, embodiments using “an olefin” include embodiments using one, two, or more olefins.

[0034] The terms “weight%” mean percentage by weight, “volume%” means percentage by volume, “mol%” means percentage by mole, and “ppm” means parts per million. “Weight ppm” and “wppm” are used interchangeably and mean parts per million on a weight basis. All concentrations herein, unless otherwise stated, are expressed on a total basis for the compositions discussed.

[0035] The term "α-olefin" refers to any linear or branched carbon and hydrogen compound having at least one double bond between an α-carbon atom and a β-carbon atom. For the purposes of this specification and the appended claims, when a polymer or copolymer is referred to as "poly-α-olefin," the α-olefin present in such a polymer or copolymer is the polymerized form of that α-olefin. Furthermore, the term "amorphous poly-α-olefin" refers to a poly-α-olefin in which the polymer chains are not arranged in an ordered crystalline configuration.

[0036] The term "polymer" refers to any two or more identical or different repeating units / monomer units or units. The term "homopolymer" refers to a polymer having identical units. The term "copolymer" refers to a polymer having two or more different units, and may refer to interpolymers, terpolymers, etc. The term "terpolymer" refers to a polymer having three different units. When referring to units, the term "different" indicates that the units differ from each other by at least one atom or are isomerically different. Similarly, as used herein, the definition of a polymer includes homopolymers, copolymers, etc. By way of example, when a copolymer is said to have 10% to 30% by weight of "propylene," it should be understood that the repeating units / monomer units, or simply units, in the copolymer are derived from propylene in the polymerization reaction, and the derived units are present at 10% to 30% by weight based on the weight of the copolymer.

[0037] As used herein, the term “monomer” or “comonomer” refers to the monomer used to form the polymer, i.e., the unreacted compound in its prepolymerization form, and may also refer to the monomer after it has been incorporated into the polymer, also referred to herein as “[monomer]-derived unit”.

[0038] The term "solution polymerization" refers to a polymerization method in which the polymer is dissolved in a liquid polymerization medium (e.g., an inert solvent, monomers (one or more), or blends thereof). Solution polymerization is typically homogeneous. The term "homogeneous polymerization" refers to a polymerization method in which the polymer product is dissolved in a polymerization medium. As described in J. Vladimir Oliveira, C. Dariva, and JCPinto, Ind. Eng. Chem. Res., 29, 2000, 4627, such a system is preferably not turbid. Homogeneous polymerization methods are typically methods in which at least 90% by weight of the product is soluble in the reaction medium.

[0039] As used herein, “Mn” refers to the number-average molecular weight of the different polymers in the polymeric material, “Mw” refers to the weight-average molecular weight of the different polymers in the polymeric material, and “Mz” refers to the z-average molecular weight of the different polymers in the polymeric material. The terms “molecular weight distribution” (MWD) and “polydispersity index” (PDI) are used interchangeably to refer to the ratio of Mw to Mn. Unless otherwise specified, all molecular weights (e.g., Mw, Mn, Mz) are reported in g / mol. Furthermore, the term “widely orthogonal comonomer distribution” (BOCD) refers to the distribution of comonomer content along the positive slope of log Mw of the polymer.

[0040] In the following discussion, "C" can be used as a prefix. n The abbreviation of "" refers to carbon-containing compounds such as hydrocarbons, among which n This refers to the number of carbon atoms in a compound, regardless of the number of hydrogen or heteroatoms. If a plus or minus sign is used, it specifies the presence of... n One or more carbon atoms n The range of carbon atoms or fewer. For example, "C9+" refers to a hydrocarbon compound having, for example, nine or more carbon atoms, and "C9-" refers to a hydrocarbon compound having nine or fewer carbon atoms.

[0041] The nomenclature of elements and their groups used in this article follows the periodic table adopted by the International Union of Pure and Applied Chemistry (IUPAC) since 1988. An example of the periodic table is shown on the inside cover of F. Albert Cotton et al., Advanced Inorganic Chemistry, 6th Edition (John Wiley & Sons, Inc., 1999).

[0042] A more detailed description of ethylene copolymers, methods for their preparation, and films made therefrom will now be provided. Each of the appended claims defines a separate invention, which, for infringement purposes, is considered to include the various elements or limiting equivalents specified in the claims. Depending on the context, all references to “invention” may in some cases refer only to certain specific embodiments. In other cases, it will be understood that references to “invention” will refer to the subject matter recited in one or more, but not necessarily all, claims. Each invention will now be described in more detail below, including specific embodiments, variations, and examples, but the invention is not limited to these embodiments, variations, or examples, which are included when the information in this disclosure is combined with publicly available information and technology to enable those skilled in the art to practice and use the invention.

[0043] The ethylene copolymers provided herein contain ethylene and at least one other C4-C20 comonomer. The ethylene content range for the lower ethylene content fraction is from a lower limit of 54% by weight to an upper limit of 85% by weight. The ethylene content range for the higher ethylene content fraction is from a lower limit of 60% by weight to an upper limit of 95% by weight. The ethylene content of the total copolymer ranges from a lower limit of 54% by weight to an upper limit of 85% by weight.

[0044] Comonomer

[0045] At least one other comonomer may comprise any one or more C4-C20 olefins. The C4-C20 comonomer may be linear, branched, or cyclic. Suitable C4-C20 cyclic olefins may be strained or unstrained, monocyclic or polycyclic, and may optionally include heteroatoms and / or one or more functional groups. The reactor C2 concentration may range from 0.1 to 40.0% by weight, while the reactor comonomer concentration may range from 0.1 to 40.0% by weight, based on the total contents of the reactor.

[0046] Specific examples of comonomers include butene, pentene, hexene, hepten, octene, nonene, decene, undecene, dodecene, norbornene, norbornadiene, dicyclopentadiene, cyclopentene, cycloheptene, cyclooctene, cyclooctadiene, cyclododecene, 7-oxanorbornene, 7-oxanorbornadiene, their substituted derivatives, and their isomers, preferably hexene, hepten, octene, nonene, decene, dodecene, cyclooctene, 1,5-cyclooctadiene, 1-hydroxy-4-cyclooctene, 1-acetoxy-4-cyclooctene, 5-methylcyclopentene, cyclopentene, dicyclopentadiene, norbornene, norbornadiene, and their respective homologues and derivatives, preferably norbornene, norbornadiene, and dicyclopentadiene. Preferred comonomers are butene and octene.

[0047] One or more dienes (diene comonomers) may be added to the polymerization process. The dienes may be present in the polymer produced herein at up to 10% by weight, preferably from 0.00001 to 8.0% by weight, more preferably from 0.002 to 8.0% by weight, and even more preferably from 0.003 to 8.0% by weight, based on the total weight of the composition. In some embodiments, 500 ppm or less, preferably 400 ppm or less, preferably 300 ppm or less of dienes are added to the polymerization. In other embodiments, at least 50 ppm, or 100 ppm or more, or 150 ppm or more of dienes are added to the polymerization.

[0048] Suitable diene comonomers comprise any hydrocarbon structure having at least two unsaturated bonds, preferably C4-C30, wherein at least one unsaturated bond readily incorporates into the polymer chain during chain growth. Also preferred are diene comonomers selected from α,ω-dien monomers (i.e., divinyl monomers). More preferably, the diene comonomer is a linear divinyl monomer, most preferably those containing 4-30 carbon atoms. Preferred dienes include butadiene, pentadiene, hexadiene, heptadecadiene, octadiene, nonadiene, decadiene, undecadiene, dodecadiene, tridecadiene, tetradecadiene, pentadecadiene, hexadecadiene, heptadecadiene, heptadecanadiene, octadecadiene, nonadecadiene, eicosadiene, icosadiene, icosadiene, icosadiene, tridecadiene, icosadiene, pentadecadiene, heptadecanadiene, octadecadiene, nonadecadiene, and triadecadiene. Particularly preferred dienes include 1,6-heptadiene, 1,7-octadiene, 1,8-nonadiene, 1,9-decadiene, 1,10-undecadiene, 1,11-dodecadiene, 1,12-tetadecanadiene, 1,13-tetradecadiene, and low molecular weight polybutadiene (Mw < 1000 g / mol). Preferred cyclic dienes include cyclopentadiene, 5-vinyl-2-norbornene, norbornene, 5-ethimide-2-norbornene, divinylbenzene, and dicyclopentadiene or dienes containing higher rings, with or without substituents at each ring position.

[0049] Ethylene copolymers can have a melt index (MI) of from 0.1 dg / min to about 1,000 dg / min, as measured according to ASTM D1238 (190°C, 2.16 g). The melt index range can also be from a lower limit of about 0.1, 0.5, or 1.0 to an upper limit of about 500, 700, or 1,000 dg / min. The melt index range can also be from a lower limit of about 5, 10, or 20 to an upper limit of about 120, 335, or 450 dg / min.

[0050] Ethylene copolymers may also have a wide melt index ratio (MIR) or (I) ranging from 18.0 to about 100.0. 21.6 / I 2.16 MIR can be measured according to ASTM D1238 (190°C / 2.16 kg). The MIR range can also be from a lower limit of about 20, 30, or 40 to an upper limit of about 60, 80, or 95.

[0051] Ethylene copolymers can have densities ranging from 0.850 g / cc to 0.915 g / cc, as measured according to ASTM D1505, indicating that they can act as a plasmid of elastomers and plastics in aggregate quantities. Ethylene copolymers can also have densities from about 0.860 g / cc to 0.880 g / cc. Density ranges can be from a lower limit of about 0.850, 0.855, 0.860, 0.865, or 0.870 to an upper limit of about 0.874, 0.876, 0.880, 0.900, or 0.915 g / cc.

[0052] Ethylene copolymers may have long-chain branching defined by g'avg between 0.7 and 0.99, as measured by GPC-4D. Ethylene copolymers may also have a g'Mz+1 to g'avg ratio of 0.9 to 1.0. This ratio may also range from a lower limit of 0.91, 0.92, or 0.93 to an upper limit of 0.97, 0.98, or 0.99.

[0053] Ethylene copolymers may have a reactivity ratio (r) of 0.9 or less. A =k AA / k AB The reactivity ratio can also range from 0.2 to 0.8. The reactivity ratio can also range from a lower limit of 0.2, 0.3, or 0.35 to an upper limit of 0.5, 0.65, or 0.8. The reactivity ratio can also be 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, or 0.8.

[0054] Ethylene copolymers can have MWD ranging from 1.2 to 5.0. The MWD range can also be 1.5-4.8, 1.8-4.7, 2.0-4.5 and 2.2-4.4.

[0055] Ethylene copolymers may have a branching index (g'avg) of 0.850-0.990, 0.860-0.980, 0.870-0.970, 0.870-0.960, or 0.88-0.950 as measured by GPC-4D.

[0056] catalyst system

[0057] Catalyst systems for polymerizing ethylene copolymers may include a single-bridged metallocene compound having a single-substituted carbon or silicon atom in one of two auxiliary monoanionic ligands (e.g., substituted or unsubstituted cyclopentadienyl (Cp) ligands and / or substituted and unsubstituted group 13-16 heteroatom ligands) at the bridging metallocene center. The bridging substituent may be a substituted aryl group, including at least one solubilized alkylsilyl substituent located on at least one aryl bridging substituent. Substituents present on the cyclopentadienyl and / or heteroatom ligands may include C1-C1 substituents. 30Hydrocarbon, alkylsilyl, or hydrofluorocarbyl groups serve as substitutions for one or more hydrogen groups on ligands or for those on fused aromatic rings on cyclopentadienyl rings. The aromatic ring can be a substituent on the cyclopentadienyl ligand and includes indenyl and fluorenyl derivatives of the cyclopentadienyl group and their hydrogenated counterparts. Such aromatic rings typically include one or more aromatic ring substituents selected from linear, branched, cyclic, aliphatic, aromatic, or combinatorial structural groups, including fused rings or side-connected structures. Examples include methyl, isopropyl, n-propyl, n-butyl, isobutyl, tert-butyl, neopentyl, phenyl, n-hexyl, cyclohexyl, benzyl, and adamantyl. As used herein, the term "hydrocarbon" or "alkyl" means to include compounds or groups that are inherently hydrocarbon-like but optionally contain no more than about 10 mol% of non-carbon heteroatoms such as boron, silicon, oxygen, nitrogen, sulfur, and phosphorus. Additionally, the term means to include hydrofluorocarbyl substituents. Examples of "alkylsilyl" include, but are not limited to, dialkylsilyl and trialkylsilyl, wherein the preferred alkyl group is a C1-C alkyl group used to bridge the phenyl group. 30 Substituted hydrocarbon, alkylsilyl, or hydrofluoroalkyl substituents. For catalysts containing heteroatoms, see International Publication No. WO 92 / 00333. Furthermore, heteroatom-containing rings or fused rings in which one of the ring atoms is replaced by a non-carbon group 13, 14, 15, or 16 atom are considered herein to be within the terms “cyclopentadienyl,” “indenyl,” and “fluorenyl.” See, for example, the background and teachings of International Publications WO 98 / 37106 and WO 98 / 41530, which are incorporated herein by reference.

[0058] Particularly suitable cyclopentadienyl-based complexes are compounds, isomers, or mixtures of (p-trimethylsilylphenyl)(p-n-butylphenyl)methylene(fluorenyl)(cyclopentadienyl)dimethylhafnium, di(p-trimethylsilylphenyl)methylene(2,7-di-tert-butylfluorenyl)(cyclopentadienyl)dimethylhafnium, di(p-triethylsilylphenyl)methylene(2,7-di-tert-butylfluorenyl)(cyclopentadienyl)dimethylhafnium, (p-triethylsilylphenyl)(p-tert-butylphenyl)methylene(2,7-di-tert-butylfluorenyl)(cyclopentadienyl)dimethyl or dibenzylhafnium, and di(p-triethylsilylphenyl)methylene(2,7-dimethylfluorenyl)(cyclopentadienyl)dimethyl or dibenzylhafnium.

[0059] Activator

[0060] Bridged metallocene compounds can be activated in any way sufficient to allow coordination or cationic polymerization as polymerization catalysts. Coordination polymerization can be achieved when one ligand is abstracted and another ligand will allow insertion into an unsaturated monomer, or similarly when a ligand that can be abstracted is replaced by a ligand that allows insertion into an unsaturated monomer (an unstable ligand, such as an alkyl, silyl, or hydrogen group). Conventional activators in the field of coordination polymerization are, for example, suitable Lewis acids such as aluminoxane compounds, and ionized anionic precursor compounds that abstract a ligand thereby ionize the bridged metallocene center into a cation and provide a balancing uncoordinated anion.

[0061] In any embodiment, the activator of the catalyst system disclosed herein may include an anionic component [Y]. In any embodiment, the anionic component may be a noncoordinate anion (NCA) having the formula [B(R] 4 )4] - , where R 4 It is an aryl group or a substituted aryl group, wherein one or more substituents are the same or different and selected from the following: alkyl, aryl, halogen atom, halogenated aryl and haloalkylaryl groups. Substituents may be perhalogenated aryl groups or perfluorinated aryl groups, including perfluorophenyl, perfluoronaphthyl and perfluorobiphenyl.

[0062] Commonly, the cationic and anionic components of the catalyst systems disclosed herein form activator compounds. In any embodiment, the activator may be N,N-dimethylphenylammonium tetra(perfluorophenyl)boronate, N,N-dimethylphenylammonium tetra(perfluoronaphthyl)boronate, N,N-dimethylphenylammonium tetra(perfluorobiphenyl)boronate, N,N-dimethylphenylammonium tetra(3,5-bis(trifluoromethyl)phenyl)boronate, or triphenylcarbon tetra(perfluorophenyl)boronate. Triphenylcarbon tetra(perfluoronaphthyl)boronic acid Triphenylcarbon tetra(perfluorobiphenyl)borate Or tetra(3,5-bis(trifluoromethyl)phenyl)boronic acid triphenylcarbon .

[0063] See also international publications WO / 2000 / 024793, WO / 2021 / 162748 and WO / 2013 / 134038, each of which is incorporated herein by reference for a detailed description of suitable catalyst systems and activators.

[0064] Preparation method

[0065] Ethylene copolymers can be prepared using solution polymerization. Preferably, solution polymerization is a bulk polymerization method, meaning a polymerization method in which the monomers and / or comonomers being polymerized are used as solvents or diluents, with little or no use of inert solvents as liquids or diluents. A small portion of the inert solvent can be used as a carrier for catalysts and scavengers. Suitable solution polymerization methods are generally described in more detail in U.S. Patent Nos. 9,359,535, 7,470,118, 7,226,553, and 7,033,152, all of which are incorporated herein by reference.

[0066] Any suitable solution polymerization reaction system can be used. For example, WO 2017 / 058385A1 describes a solution polymerization method for the continuous polymerization of C2-C40 olefins using a single or multiple spiral heat exchanger system, which is also applicable and is incorporated herein by reference in its entirety.

[0067] In one embodiment, the reactor system may include one or more plug flow reactors, and each plug flow reactor may be or may include at least one helical heat exchanger. The helical heat exchanger may include a body formed by winding at least one helical blade to form a helix, the helix being arranged radially about the axis of the helical heat exchanger. The helix may form at least one flow channel for the flow of the heat exchange medium, and the helix may be surrounded by a substantially cylindrical shell. Furthermore, the cylindrical shell may include at least one inlet and at least one outlet in fluid communication with the at least one flow channel for supplying and removing the heat exchange medium.

[0068] Monomers, comonomers, catalyst systems, and copolymer products flow axially through channels formed between the spirals of the heat exchanger. The monomers, comonomers, catalyst systems, and copolymer products also flow in a cross-flow direction relative to the spiral of at least one spiral heat exchanger. As used herein, "cross-flow" means flow in a direction substantially orthogonal to the spiral of at least one spiral heat exchanger. Substantially orthogonal may include flow of monomers, comonomers, catalyst systems, and copolymer products at angles of 70° to 110°, preferably 80° to 100°, more preferably 85° to 95°, even more preferably 88° to 92°, or most preferably 90°, relative to the spiral of at least one spiral heat exchanger.

[0069] At least one helical heat exchanger may be oriented in a substantially vertical direction, such that monomers, comonomers, catalyst systems, and copolymer products flow through at least one helical heat exchanger in a substantially vertical direction. The orientation of the at least one helical heat exchanger is not limited to such a vertical orientation, but rather can be oriented in any direction, as long as the feed and product flow through at least one helical heat exchanger in a cross-flow direction relative to the helix of the at least one helical heat exchanger. For example, at least one helical heat exchanger may be oriented in a substantially horizontal direction, such that monomers, comonomers, catalyst systems, and copolymer products flow through at least one helical heat exchanger in a substantially horizontal direction.

[0070] Alternatively, at least one spiral heat exchanger may include multiple spiral heat exchangers, such as at least 2, at least 3, at least 4, at least 5, at least 6, at least 7, at least 8, at least 9, at least 10, at least 11, at least 12, at least 13, at least 14, at least 15, at least 16, at least 17, at least 18, at least 19, at least 20, at least 21, at least 22, at least 23, at least 24, etc.

[0071] At least one spiral heat exchanger used in the method described herein may be any suitable spiral heat exchanger known in the art. Non-limiting examples of suitable spiral heat exchangers include those described in U.S. Patent Nos. 8,622,030, 8,075,845, 8,573,290, 7,640,972, 6,874,571, 6,644,391, 6,585,034, and 4,679,621; U.S. Publications Nos. 2010 / 0170665, 2010 / 0008833, 2002 / 0092646, and 2004 / 0244968; and International Publication No. WO / 2017 / 058385, each of which is incorporated herein by reference. Additionally or alternatively, at least one spiral heat exchanger may have a surface area to volume ratio of about 20-30 ft² / ft³. Advantageously, the spiral heat exchanger may have an open passage height of 0.5 to 30 feet, preferably 1 to 25 feet, 3 to 20 feet, 5 to 15 feet, or 5 to 10 feet.

[0072] The heat exchange medium flowing through the spiral of the heat exchanger can be any suitable heat exchange medium known in the art. Particularly useful heat exchange media are those that are stable at the reaction temperature and generally include those that are stable at 200°C or higher. Examples of heat exchange media include water and other aqueous solutions, oils (e.g., hydrocarbons such as mineral oil, kerosene, hexane, pentane, etc.), and synthetic media, for example, those available from The Dow Chemical Company (Midland, Michigan) under the trademark DOWTHERM. TMCommercially available polymers, such as those with designations A, G, J, MX, Q, RP, and T, are used. If water is used, it is preferably at a suitable pressure to prevent boiling. Preferably, the heat exchange medium flows through the spiral at a temperature lower than the feed stream temperature. Alternatively or alternatively, the heat exchange medium may flow through the spiral at a temperature higher than the polymer's precipitation point. For example, the heat exchange medium may flow through the spiral at a temperature of 100°C to 150°C, preferably 120°C to 140°C, or more preferably 130°C.

[0073] In all respects, the monomers, comonomers, catalyst systems, and polymers can be maintained essentially as a single liquid phase under polymerization conditions. Preferably, the liquid flow through at least one helical heat exchanger can be substantially laminar or near-laminar. Preferably, the Reynolds number of the liquid flow can be > about 0.1, > about 1.0, > about 10.0, > about 20.0, > about 30.0, > about 40.0, > about 50.0, > about 60.0, > about 70.0, > about 80.0, > about 90.0, > about 100, > about 200, > about 300, > about 400, > about 500, > about 600, > about 700, > about 800, > about 900, > about 1,000, > about 1,100, > about 1,200, > about 1,300, > about 1,400, > about 1,500, > about 1,600, > about 1,700, > about 1,800, > about 1,900, > about 2,000, > about 2,100, or about 2,200. Alternatively, the Reynolds number for the liquid flow may be <approximately 40.0, <approximately 50.0, ≤approximately 60.0, ≤approximately 70.0, ≤approximately 80.0, ≤approximately 90.0, ≤approximately 100, ≤approximately 200, <approximately 300, ≤approximately 400, ≤approximately 500, ≤approximately 600, ≤approximately 700, ≤approximately 800, ≤approximately 900, ≤approximately 1,000, ≤approximately 1,100, ≤approximately 1,200, ≤approximately 1,300, ≤approximately 1,400, ≤approximately 1,500, ≤approximately 1,600, ≤approximately 1,700, ≤approximately 1,800, ≤approximately 1,900, ≤approximately 2,000, ≤approximately 2,100, or <approximately 2,200. The explicitly disclosed range includes any combination of the values ​​listed above, such as about 0.1 to about 2,200, about 1.0 to about 1,400, about 1.0 to about 100, about 50.0 to about 900, etc. Preferably, the Reynolds number of the liquid is about 0.1 to about 2,200, more preferably about 1.0 to about 1,000, more preferably about 1.0 to about 100, and more preferably about 1.0 to about 50. The Reynolds number is calculated using the hydraulic diameter (Dh) and is defined as Dh = 4A / P, where P is the wetted perimeter of the cross-section of the channel in the helical heat exchanger and A is the cross-sectional area. When using a non-Newtonian fluid, zero shear viscosity is used for Reynolds number calculation.

[0074] The polymerization process can be carried out at temperatures ranging from about 50°C to about 220°C, preferably from about 70°C to about 210°C, preferably from about 90°C to about 200°C, preferably from about 100°C to about 190°C, or preferably from about 130°C to about 160°C. The polymerization process can be carried out at pressures ranging from about 120 to about 1,800 psi (827 to 12,411 kPa), preferably from about 200 to about 1,000 psi (1,379 to 6,895 kPa), preferably from about 300 to about 800 psi (2,068 to 5,516 kPa).

[0075] In all respects, the residence time in a spiral heat exchanger can be up to 24 hours or longer, typically from about 1 minute to about 15 hours. Preferred residence times are about 2 minutes to about 1 hour, about 3 to about 30 minutes, about 5 to about 25 minutes, or about 5 to about 20 minutes.

[0076] In some embodiments, hydrogen may be present during the polymerization process at a partial pressure of about 0.001 to about 50,000 psig (0.007 to 346 kPa), preferably about 0.010 to about 25,000 psig (0.069 to 172 kPa), and more preferably about 0.100 to about 10,000 psig (0.689 to 483 kPa). Alternatively, the hydrogen concentration in the feed may be 500 wppm or less, preferably 200 wppm or less.

[0077] In all respects, the resulting polymer may have a cement concentration ranging from about 2% to about 40% by weight, preferably from about 6% to about 40% by weight, or more preferably from about 6% to about 25% by weight. The cement concentration may also be at least 5%, 8%, 10%, 15% or 25% and less than 40% by weight. “Cement concentration” is defined herein as the weight of the polymer produced based on the weight of the total solvent (e.g., monomers, comonomers and / or solvents).

[0078] Monomers, comonomers, catalyst systems, and solvents can be added and reacted within the reactor to produce ethylene copolymer products. Other embodiments are described below in the experimental section and referenced. Figure 6 and 8 Explanation: A portion of the monomer, comonomer, and / or catalyst system can be premixed and reacted upstream or downstream of the reactor to influence the weight ratio of ethylene to comonomer, thereby producing a high-density (HD) fraction in the copolymer product. For example, a small portion of the monomer, comonomer, and catalyst system can be reacted in the conduit section upstream of the reactor to produce a prepolymer, such as... Figure 6The process is described in [description missing], and then fed into the reactor system. In some embodiments, any proportion of 5-45% by weight of the total amount of catalyst and activator may be added to the upstream conduit of the solution polymerization reactor. 5-45% by weight of the total amount of ethylene may be added to the upstream conduit of the solution polymerization reactor. 5-45% by weight of the total amount of comonomer may be added to the upstream conduit of the solution polymerization reactor. At least 90% by weight of the ethylene copolymer may be prepared in the solution polymerization reactor, and the balance of the ethylene copolymer may be prepared in the upstream conduit of the solution polymerization reactor. Alternatively, monomers may be added downstream of the reactor alone or together with additional comonomers and / or catalysts and / or activators, thereby affecting the weight ratio of ethylene to comonomers, thereby producing a high-density (HD) fraction in the copolymer product, such as [description missing]. Figure 8 As described in the description. In some embodiments, any proportion of 5-45% by weight of the total amount of catalyst and activator may be added to a conduit downstream of the solution polymerization reactor. 5-45% by weight of the total amount of ethylene may be added to a conduit downstream of the solution polymerization reactor. 5-45% by weight of the total amount of comonomer may be added to a conduit downstream of the solution polymerization reactor. At least 90% by weight of the ethylene copolymer may be prepared in the solution polymerization reactor, and the balance of the ethylene copolymer may be prepared in a conduit downstream of the solution polymerization reactor.

[0079] The polymerization method may also include recycling at least a portion of the solvent, monomer / comonomer, catalyst system, and polymer leaving the reactor back through the reactor. Recycling ratios in the range of about 3 to about 50, preferably about 3 to about 30, or more preferably about 3 to about 20, can be used to produce the polymer. The recycling ratio is defined herein as the ratio of the flow rate of the recirculation loop just before entering the spiral heat exchanger (alone or in series) to the flow rate of the fresh feed to the spiral heat exchanger (alone or in series).

[0080] Ethylene copolymers may have any two or more unique combinations of the following properties:

[0081] Density ranging from 0.850 g / cc to 0.915 g / cc;

[0082] MI from 0.1 dg / min to 1000 dg / min;

[0083] 18 to 100 MIR (I 21.6 / I 2.16 );

[0084] TREF elution peak 1 is the major fraction accounting for more than 90% by weight of the total composition;

[0085] TREF elution peak 1 from 0℃ to 80℃;

[0086] TREF elution peak 2 is a minor fraction accounting for less than 8% by weight of the total composition;

[0087] TREF elution peak 2 at 60℃ to 95℃;

[0088] MWD of 1.2 to 5.0; and

[0089] The branching index (g'avg) is 0.850-0.990 as measured by GPC-4D.

[0090] Other testing methods

[0091] Film thickness was measured using a Measuretech Series 200 instrument and reported in micrometers. The instrument uses a capacitance meter to measure film thickness. For each film sample, ten film thickness data points were measured per inch of film as the film passed laterally through the gauge. From these measurements, the average film thickness measurement was determined and reported.

[0092] Gel permeation chromatography (GPC) is a liquid chromatography technique used to measure the molecular weight and polydispersity of polymers.

[0093] Unless otherwise indicated, the moments and distributions of molecular weights (e.g., Mw, Mn, Mz, Mw / Mn) and the content of comonomers (e.g., C2, C3, C6) were determined by high-temperature gel permeation chromatography (Polymer Char GPC-IR) using an infrared detector IR5 equipped with a multi-channel bandpass filter, an 18-angle light scattering detector, and a viscometer. Polymer separation was provided using three Agilent PLgel 10-μm mixed-B LS columns. Aldrich reagent-grade 1,2,4-trichlorobenzene (TCB) with 300 ppm of the antioxidant butylated hydroxytoluene (BHT) was used as the mobile phase. The TCB mixture was filtered through a 0.1-μm Teflon filter and degassed using an in-line degasser before entering the GPC instrument. The nominal flow rate was 1.0 mL / min, and the nominal injection volume was 200 μL. The entire system, including the transfer lines, columns, and detector, was housed in an oven maintained at 145 °C. Weigh the polymer sample and seal it in a standard vial containing 80 μL of flow marker (heptane). After loading the vial into the autosampler, dissolve the polymer in an instrument containing 8 mL of added TCB solvent. Dissolve the polymer by continuously shaking for approximately 1 hour at 160 °C for polyethylene samples or approximately 2 hours for polypropylene samples. The TCB density used for concentration calculation is 1.463 g / mL at room temperature and 1.284 g / mL at 145 °C. Sample solution concentrations range from 0.2 to 2.0 mg / mL, with lower concentrations used for higher molecular weight samples. The IR5 broadband signal intensity is calculated by subtracting the baseline. I) The following equation is used to calculate the concentration at each point in the chromatogram ( c ): c = βI ,in β It is a mass constant. The mass recovery can be calculated from the ratio of the integral area of ​​the concentration chromatography within the elution volume to the injection mass (which is equal to the predetermined concentration multiplied by the injection loop volume). The conventional molecular weight (IR molecular weight) is determined by combining a universal calibration relationship with column calibration (which uses a range of monodisperse polystyrene (PS) standards ranging from 700 to 10,000,000 gm / mol). The molecular weight in each elution volume is calculated using (1):

[0094] Equation 1

[0095] Variables with the subscript "PS" represent polystyrene, while those without subscripts represent the test sample. In this method, αPS = 0.67 and KPS = 0.000175, while as disclosed and calculated in the literature (Sun, T. et al. Macromolecules 2001, 34, 6812) for other materials, except for the purposes of this invention and the appended claims, α = 0.705 and K = 0.0002288 for linear propylene polymers, α = 0.695 and K = 0.000181 for linear butene polymers, and α is 0.695 and K is 0.000579 for ethylene-butene copolymers. (1-0.0087 w2b+0.000018 (w2b)^2 (where w2b is the bulk weight percentage of the butene comonomer), for the ethylene-hexene copolymer, α is 0.695 and K is 0.000579. (1-0.0075 w2b)(where w2b is the bulk weight percentage of the hexene comonomer), and for the ethylene-octene copolymer, α is 0.695 and K is 0.000579. (1-0.0077 w2b)(where w2b is the bulk weight percentage of the octene comonomer), and for all other linear ethylene polymers α = 0.695 and K = 0.000579. Unless otherwise specified, concentrations are expressed in g / cm³. 3 The units are expressed as follows: molecular weight is expressed in g / mol, and intrinsic viscosity (and therefore K in the Mark-Houwink equation) is expressed in dL / g.

[0096] The comonomer composition is determined by the ratio of the intensity of an IR5 detector corresponding to the CH2 and CH3 channels (calibrated using a series of polyethylene and propylene homopolymer / copolymer standards with predetermined nominal values ​​by NMR or FTIR). Specifically, this provides methyl groups per 1000 total carbons (CH3 / 1000TC) as a function of molecular weight. The short-chain branching (SCB / 1000TC) content per 1000TC as a function of molecular weight can then be calculated by applying chain-end correction to the CH3 / 1000TC function, assuming each chain is linear and capped at each end with a methyl group. The comonomer weight percentage can then be obtained from the following expression, where for comonomers such as C3, C4, C6, C8, etc. These are 0.3, 0.4, 0.6, and 0.8, respectively.

[0097] Equation 2

[0098] The bulk composition of the polymer from GPC-IR and GPC-4D analyses was obtained by considering the entire signal of the CH3 and CH2 channels between the integration limits of the concentration chromatogram. First, the following ratios were obtained.

[0099] Equation 3

[0100] Then, a correction for the CH3 and CH2 signal ratios being equal (as mentioned previously in obtaining CH3 / 1000TC as a function of molecular weight) is applied to obtain the bulk CH3 / 1000TC. The bulk methyl end / 1000TC (bulk CH3 end / 1000TC) is obtained by weighted average chain-end correction over the molecular weight range.

[0101] Equation 4

[0102] Equation 5

[0103] Convert the SCB / 1000TC to the main body in the same way as described above. .

[0104] The LS detector is an 18-angle Wyatt Technology High Temperature DAWN HELEOSII. The molecular weight (M) of the LS at each point in the chromatogram was determined by analyzing the LS output using a Zimm model for static light scattering (Light Scattering from Polymer Solutions, Huglin, MB ed., Academic Press, 1972).

[0105] Equation 6

[0106] Here, ΔR(θ) is the scattering angle. The excess Rayleigh scattering intensity measured at θ, c is the polymer concentration determined from IR5 analysis, A2 is the second virial coefficient, P(θ) is the shape factor of the monodisperse random coil, and KO are the optical constants of the system.

[0107] Equation 7

[0108] Where NA is Avogadro's constant, and (dn / dc) is the refractive index increment of the system, with n=1.500 for TCB at 145℃ and λ=665nm. For the analysis of ethylene homopolymers, ethylene-hexene copolymers, and ethylene-octene copolymers, dn / dc=0.1048 ml / mg and A2=0.0015; for the analysis of ethylene-butene copolymers, dn / dc=0.1048 (1-0.00126 w2) ml / mg and A2=0.0015, where w2 is the weight percentage of the butene comonomer, and dn / dc=0.1048 ml / mg and A2=0.0015 for all other ethylene polymers.

[0109] Specific viscosity is determined using a high-temperature viscometer, such as those manufactured by Technologies, Inc. or Viscotek Corporation (which have 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, placed between the two sides of the bridge, measures the pressure difference. The specific viscosity ηs of the solution flowing through the viscometer is calculated from their outputs. The intrinsic viscosity [η] at each point in the chromatogram is calculated using the equation [η] = ηs / c, where c is the concentration and is determined by the IR5 wideband channel output. The viscosity MW at each point is calculated as follows: ,in The ps value is 0.67 and the Kps value is 0.000175. The average intrinsic viscosity of the sample is... Through the following calculations:

[0110] Equation 8

[0111] The sum is taken from all chromatographic slices i between the integration limits.

[0112] The long chain branching index (g'LCB, also known as g'vis) is defined as...

[0113] Equation 9

[0114] in The viscosity-average molecular weight, K, is corrected using polystyrene standards. For reference linear polymers, as disclosed and calculated in the literature (Sun, T. et al. Macromolecules 2001, 34, 6812), except for the purposes of this invention and the appended claims, α = 0.705 and K = 0.0002288 for linear propylene polymers, α = 0.695 and K = 0.000181 for linear butene polymers, and α is 0.695 and K is 0.000579 for ethylene-butene copolymers. (1-0.0087 w2b+0.000018 (w2b)^2 (where w2b is the bulk weight percentage of the butene comonomer), for the ethylene-hexene copolymer, α is 0.695 and K is 0.000579. (1-0.0075 w2b)(where w2b is the bulk weight percentage of the hexene comonomer), and for the ethylene-octene copolymer, α is 0.695 and K is 0.000579. (1-0.0077 w2b)(where w2b is the bulk weight percentage of the octene comonomer), and for all other linear ethylene polymers α=0.695 and K=0.0005.

[0115] Any IR or LS detector as indicated above can be used to obtain molecular weight values ​​from GPC. LS detectors are used for molecular weight values ​​indicated herein unless otherwise specifically stated as being from an IR detector. However, we also specifically indicate in many cases that LS detectors are used for molecular weight values ​​– for example, the weight-average molecular weight determined using an LS detector can be expressed as Mw(LS). Furthermore, the weight percentage of all comonomers as measured at a specific molecular weight value (e.g., the weight percentage of comonomers at Mw and / or Mn and / or Mz) is determined based on the molecular weight value as determined using an LS detector. Alternatively, an IR detector is used when a technician sees Mz(IR), Mw(IR), etc.

[0116] The TREF technique was performed as described in Wild et al., J. Poly. Sci., Poly. Phys. Ed., Vol. 20, p. 441 (1982) and U.S. Patent No. 5,008,204, which is incorporated herein by reference. For measurements, a temperature range of 0°C to 140°C was used for all samples with a crystallization heating rate of 1°C / min and an elution heating rate of 2°C / min. The cumulative curves provide the weight % change across the elution temperature range and the weight % of the high density (HD) from each sample.

[0117] The puncture fracture energy and peak puncture force at break can be measured using the procedure written in the standard test method of ASTM F1306. The specimen (6” × 6”) is placed in the clamping device. A probe is inserted into the membrane at a constant rate of 10 in / min. At least five specimens should be tested for each sample.

[0118] The following measurements were taken to determine the top load, permanent deformation, and 50% recovery force. A 50 mm × 100 mm test sample was stretched to 100% elongation at 500 mm / min. At 100% elongation, the sample was held for 1 second, then returned to its starting position at the same speed of 500 mm / min. The sample was held for 30 seconds, and the elongation cycle was repeated a second time. The test was conducted at 20°C and 50% relative humidity. Permanent deformation is the increase in length, expressed as a percentage of the sample's original length, meaning that once the load is removed, the sample cannot return to its original length after each elongation cycle. For example, 0% permanent deformation means that the sample fully recovers to its original length after elongation, while 100% permanent deformation means that the sample shows no elastic recovery after elongation. Peak load (N) is the force at 100% elongation, while the shrinkage force at 50% recovery is the force applied to the sample at 50% elongation, measured when the sample shrinks back from 100% elongation and expressed in N. The values ​​of peak load (N), permanent deformation (%), and shrinkage force (N) are measured from the first and second cycles of the test.

[0119] The Izod impact strength is determined using a procedure based on the ISO 180 method. All specimens are conditioned for at least four hours at the specified test temperature (-30°C, -20°C, 23°C) prior to testing. Impact resistance is reported in kJ / m². The Charpy impact test is performed based on the procedure in ISO 179 and measures resistance to pendulum impact. Specimens with dimensions of 80 × 10 mm are mounted horizontally without clamps or supports at both ends. The hammer is released and allowed to penetrate the specimen. The impact energy absorbed by the specimen at the notched cross-sectional area is expressed in kilojoules per square meter (kJ / m²). Specimens to be tested at temperatures below ambient (0°C, -20°C, -30°C, and -40°C) must be conditioned for at the required temperature in a chamber below ambient temperature for at least four hours.

[0120] The thermal deflection temperature (°C) is based on the procedure outlined in ISO 75 Method B and is the temperature at which pre-deformation occurs under specified load and temperature.

[0121] Flexural modulus was measured according to procedure ISO 178 using a deformation rate of 0.08 in / min. Dart impact strength (DIS) was reported in grams (g), (g / mil), or (g / μm) and measured according to ASTM D-1709, Method A. The dart head was made of phenolic resin. The impact failure weight was calculated as the weight of 50% of the test specimen that would fail under impact.

[0122] Tear tests were performed on the longitudinal and transverse upper films using the ASTM D 1922–15 method on the ProTear Elmendorf tear tester. Ten specimens were tested, and the average value in grams was reported from these measurements.

[0123] Haze was measured using the HazeGard PLUS haze meter according to ASTM D1003. Haze is the percentage of transmitted light that passes through the membrane at a deflection greater than 2.5°. At least three membrane samples were tested, and the average (%) of these test results was reported.

[0124] The heat seal initiation temperature can be measured using ASTM F1921. The heat seal initiation temperature is the temperature at which a heat seal forms immediately after the sealing operation. The strength of the heat seal is measured at specified time intervals (milliseconds) after the sealing cycle is completed and the seal has cooled to ambient temperature and reached its maximum strength. The strength of the seal is typically specific; for example, a heat seal initiation temperature of 1 lb refers to the temperature at which such a seal forms and will have a strength of 1 lb force.

[0125] "Heat-adhesive seal initiation temperature" is the temperature at which a heat seal is formed immediately after the sealing operation. The strength of the heat seal is measured at specified time intervals (milliseconds) after the sealing cycle is completed and before the seal has cooled to ambient temperature and reached its maximum strength. The strength of the seal is typically specific; for example, "heat-adhesive seal initiation temperature at 2 N" refers to the temperature at which a 2 N heat seal is formed. The heat-adhesive seal initiation temperature can be measured using ASTM F1921.

[0126] The Vicat softening temperature was measured using a Ceast HDT 3 Vicat instrument. Specimens with thicknesses between 3 mm and 6.5 mm and a minimum square or diameter of 10 mm were used. Three specimens were conditioned in a controlled temperature and humidity laboratory according to ASTM D618 requirements (23°C ± 2°C and 50 ± 10% relative humidity). The reported Vicat temperatures were obtained under a 200 gm load perpendicular to the test specimen, using a selected uniform rate of 50°C / hr, 1-mm. 2 The temperature at which a flat-headed needle with a circular cross-section penetrates a thermoplastic specimen to a depth of 1 mm.

[0127] Example:

[0128] The foregoing discussion can be further described with reference to the following non-limiting examples. In the following examples, ethylene copolymers (“ECP”) made from octene comonomers and having a density range of 0.850 g / cc to 0.902 g / cc and a melt index range of 0.3 to 200 MI were prepared according to the embodiments provided herein. ECP is compared with various commercially available EO copolymers having similar densities and MIs.

[0129] Comparative Example 1 (C1) is a Fortify C1055D ethylene octene copolymer from SABIC, with a density of 0.857 g / cc and a melt index of 1.0 g / 10 min.

[0130] Comparative Example 2 (C2) is an ethylene octene copolymer from LGChem with a density of 0.857 g / cc and a melt index of 1.0 g / 10 min.

[0131] Comparative Example 3 (C3) is Engage 8842 ethylene-octene copolymer from The Dow Chemical Company, with a density of 0.857 g / cc and a melt index of 1.0 g / 10 min.

[0132] Comparative Example 4 (C4) is Queo 6201 ethylene octene copolymer from Borealis, with a density of 0.862 g / cc and a melt index of 1.0 g / 10 min.

[0133] Comparative Example 5 (C5) is Engage 8100 ethylene octene copolymer from The Dow Chemical Company, with a density of 0.870 g / cc and a melt index of 1.0 g / 10 min.

[0134] Comparative Example 6 (C6) is Engage 8200 ethylene octene copolymer from The Dow Chemical, which has a density of 0.870 g / cc and a melt index of 5.0 g / 10 min.

[0135] Comparative Example 7 (C7) is Exact 5171 ethylene octene copolymer from ExxonMobil Chemical, with a density of 0.868 g / cc and a melt index of 1.0 g / 10 min.

[0136] Comparative Example 8 (C8) is Exact 5371 ethylene octene copolymer from ExxonMobil Chemical, with a density of 0.868 g / cc and a melt index of 5.0 g / 10 min.

[0137] Comparative Example 9 (C9) is Exact 5101 ethylene octene copolymer from ExxonMobil Chemical, with a density of 0.900 g / cc and a melt index of 1.1 g / 10 min.

[0138] Comparative Example 10 (C10) is Affinity PL1880G ethylene octene copolymer from The Dow Chemical, with a density of 0.902 g / cc and a melt index of 1.0 g / 10 min.

[0139] ECP S27-S31 was produced in a pilot-scale solution reactor using di(p-triethylsilylphenyl)methylene(2,7-di-tert-butylfluorenyl)(cyclopentadienyl)dimethylhafnium, available from ExxonMobil Chemical Company, as a catalyst and N,N-dimethylphenylammonium tetra(heptafluoronaphthyl)boronic acid as a co-catalyst / activator. Table 1 shows the physical properties and molecular weights of the ECPs, as measured according to the test procedures described herein. Table 2 shows the physical properties and molecular weights of various commercially available copolymers with similar densities and molecular weights.

[0140] Table 1: Physical properties of ethylene copolymers and Mw

[0141]

[0142]

[0143] Table 2: Physical properties and Mw of commercially available copolymers

[0144]

[0145] Figure 1 The TREF composition curves for the lower-density copolymers shown in Table 1 are S27 and C3 (Engage 8842), C1 (Fortify C1055D), and C4 (Queo 6201). The comparative copolymers with densities ranging from 0.857 to 0.862 g / cc exhibit a single peak at low elution temperatures (0–30 °C), while S27 (0.861 g / cc) shows a dominant peak at both low elution temperatures (0–30 °C) and approximately 70 °C. Surprisingly, the presence of this 70 °C peak (0.1–5 wt% of the total fraction) did not significantly alter the molecular weight or other physical properties of the copolymers; that is, the density, molecular weight (MI), and Vicat softening temperature (39 °C) were comparable to the corresponding properties of C2 (37 °C) and C3 (41 °C).

[0146] Figure 2 shows the TREF composition curves of the copolymers with medium densities in Table 1, namely S22 and S31 and the comparative copolymers C5 (Engage 8100) and C6 (Engage 8200), C7 (Exact 5171) and C8 (Exact 5371). The comparative copolymers with densities ranging from 0.866 to 0.872 g / cc exhibit a single peak at low elution temperatures (0–30 °C), while S22 and S31 (0.866 and 0.868 g / cc) have dominant peaks at both low elution temperatures (0–30 °C) and approximately 70 °C. The presence of this 70 °C peak (0.1 to 5 wt% of the overall fraction) is also surprisingly not significantly altered in terms of molecular weight or other physical properties of the copolymers, such as density, MI, and Vicat softening temperature (49 °C for S22 and 53 °C for S31, 54 °C for C7 and 51 °C for C8).

[0147] Figure 3 TREF composition curves show a comparison between the higher-density copolymers (S14 and S21) and commercially available C9 (Exact5101) and C10 (Affinity PL1880G) with similar densities. (See from...) Figure 3 The TREF composition curves indicate that ECP S14 and S21 have two peaks: one in the lower elution temperature (higher C8%) region and the other at a higher elution temperature (70°C), while the comparative copolymers only have a single peak at low elution temperatures (0-30°C). Similar to S27, S22, and S31, the molecular weight and density, MI, and Vicat softening temperature are surprisingly unchanged.

[0148] Figure 4 The TREF elution temperature peaks (peak 1 and peak 2) are shown as a function of ethylene weight % (%). Figure 5 The HD fraction (wt%) of the overall composition is shown as a function of the total ethylene content (wt%), and it can be seen that it decreases as the C2 wt% in the composition increases. This may be facilitated by localized reaction zones with relatively high ethylene to comonomer concentration ratios, and these zones may be close to the feed replenishment injection point.

[0149] Elastic properties

[0150] The elastic properties of the lower-density S27 were evaluated. Table 2 shows the hysteretic elastic properties of the lower-density copolymer S27 of the present invention at 100% elongation compared to the comparative example C3 of a similar density. It is noted that for the sample S27 with a higher density fraction of approximately 5.5 wt%, the elastic properties, such as peak load, shrinkage force, and permanent deformation, in the first and second cycles were surprisingly comparable to those of the comparative example C3 ethylene octene copolymer. This indicates that the presence of the higher density fraction did not significantly alter the elastic properties of the resin.

[0151] Table 2. Elastic properties from hysteresis curves at 100% elongation

[0152]

[0153] TPO performance

[0154] Using three of the aforementioned ethylene copolymers (“ECP”), namely S22, S27, and S31, TPO formulations of 20 wt% ECP, 20 wt% PP 7033, 50 wt% PP 7935, and 10 wt% talc were prepared. Table 3 below shows the low-temperature (-20°C to 30°C) impact and flexural modulus of these TPO formulations compared to commercially available copolymers with similar densities and melt indices. As reported in Table 3, the impact toughness values ​​of the TPO formulations using the high-density fraction of ECP provided herein did not show a significant deviation from the impact performance of the comparative examples. Apart from impact toughness, other mechanical properties such as flexural modulus and tensile strength showed comparable performance, while the thermal flexural temperature showed that ECP performed slightly better.

[0155] Table 3: TPO performance properties from three lower-density ECPs:

[0156]

[0157] Membrane performance

[0158] Two ECPs (S14 and S21) were fabricated into blown films, and their mechanical properties were tested to assess the effect of HD fractionation (if present). Table 4 reports the tests performed and the results, along with the extruder melt pressure and motor load. The film properties are significantly different from those of resins with different branching contents (by melt index ratio (I0.05). 21 The melt index ratio (Mw / Mn) is related to the evaluation of the molecular weight distribution (Mw / Mn). The melt index ratio of S14 ECP is 27, while that of S21 is 53. Compared with films with higher MIR (higher branching), the compositions of the present invention with lower MIR (less branching) exhibit higher film properties such as dart impact, longitudinal tear, puncture energy, and haze. Films with less branching show better properties than films with higher branching, while, as expected, processability measured by melt pressure and motor load in the film linear extruder shows the opposite trend to MIR.

[0159] Table 4 shows the sealing performance of single-layer blown films made from ECP with a density of 0.894 g / cc and a molecular weight of 1.1 MI. Surprisingly, the presence of the higher-density EO component in ECP S14 and S21 did not significantly alter the seal initiation temperature or the thermal adhesion initiation temperature.

[0160] Table 4. Properties of blown film

[0161]

[0162] Method illustration

[0163] It is believed that a high catalyst to activator ratio during the process causes the formation of such compositions with two or three TREF peaks. Figure 6 This diagram illustrates the preparation of the ECP described herein by solution polymerization using a secondary high-density (HD) fraction. As described, the ethylene feed, catalyst, and activator are typically present in the normal reactor feed of the reactor system, while a “secondary” feed with a higher C2= / Cx= concentration ratio (ethylene / comonomer) can be injected into a conduit upstream of the reactor system, where it is not immediately well mixed when introduced into the bulk contents of the reactor system. As a result, the HD fraction is produced by localized reactions at the higher C2= / Cx= concentration ratio.

[0164] Figure 7 This displays the feed rate of the high-density fraction of TREF relative to the catalyst and activator entering the reactor, expressed as a percentage by weight. Figure 7 The study showed that catalyst feed rates > 2 cc / min typically resulted in a step increase in the HD fraction. It is believed that a higher catalyst-to-activator ratio promotes localized reaction zones with relatively high ethylene-to-comonomer concentration ratios, and this zone may be close to the feed replenishment point.

[0165] Figure 8 An alternative schematic diagram is described for solution polymerization to prepare copolymers with two or three TREF peaks. In this method, additional ethylene supplementation is added downstream of the reactor system before quenching to promote further polymerization under higher C2= / Cx= ratio conditions, thereby producing the HD fraction in the resulting composition.

[0166] Other implementation plans

[0167] This disclosure may further include any one or more of the following non-limiting embodiments:

[0168] Implementation Scheme 1: An ethylene copolymer comprising: at least 60 wt% ethylene-derived units and 10-40 wt% comonomer-derived units derived from one or more C4-C20 α-olefins, wherein the copolymer has a density in the range of 0.850 g / cc to 0.915 g / cc; an MI in the range of 0.1 dg / min to 1000 dg / min; a MIR (I21.6 / I2.16) in the range of 18 to 100; and at least two TREF peaks, wherein at least one TREF peak is a major fraction comprising at least 90 wt% of the copolymer, and wherein at least one TREF peak is a minor fraction comprising less than 8 wt% of the copolymer and occurring in the range of 60°C to 95°C.

[0169] Implementation Scheme 2: The ethylene copolymer of Implementation Scheme 1, wherein the TREF peak of the major fraction appears in the range of 0°C to 80°C.

[0170] Implementation Scheme 3: The ethylene copolymer of Implementation Scheme 1 or 2, wherein the copolymer is polymerized by solution polymerization using a plug flow reactor or CSTR, and the copolymer has a sludge concentration of 6% to 40% (polymer weight / solvent weight).

[0171] Implementation Scheme 4: An ethylene copolymer of any of Implementation Schemes 1 to 3, wherein the copolymer has a MWD (Mw / Mn) of 1.2 to 5.0.

[0172] Implementation Scheme 5: An ethylene copolymer of any of Implementation Schemes 1 to 4, wherein the copolymer has a branching index of 0.850-0.990 as measured by GPC-4D.

[0173] Implementation Scheme 6: An ethylene copolymer of any of Implementation Schemes 1 to 5, wherein the copolymer is used in TPO, injection molding, elastic and film applications.

[0174] Implementation Scheme 7: An ethylene copolymer of any of Implementation Schemes 1 to 6, wherein the copolymer is polymerized in a single reactor using a single metallocene catalyst system.

[0175] Implementation Scheme 8: An ethylene copolymer of any of Implementation Schemes 1 to 7, wherein the copolymer further comprises one or more granule coating additives.

[0176] Implementation Scheme 9: An ethylene copolymer of any of Implementation Schemes 1 to 8, wherein the copolymer does not contain any added metal stearates or siloxanes.

[0177] Implementation Scheme 10: An ethylene copolymer of any of Implementation Schemes 1 to 9, wherein the copolymer does not contain any added HDPE, LDPE or talc release agent.

[0178] Implementation Scheme 11: A method for preparing copolymers by solution polymerization, comprising: (a) feeding ethylene, at least one comonomer, and a solvent in controlled proportions into a conduit upstream of a solution polymerization reactor; (b) adding a single metallocene catalyst and an activator into the conduit; (c) polymerizing at least a portion of the ethylene and at least one other monomer in the solution polymerization reactor to produce an ethylene prepolymer having at least 5% by weight of the comonomer; (d) feeding the ethylene prepolymer into the solution polymerization reactor; (e) feeding additional ethylene, comonomer, catalyst, and activator in controlled proportions and optionally additional solvent into the solution polymerization reactor; and (f) operating the solution polymerization reactor to produce an ethylene copolymer comprising: at least 60% by weight of ethylene-derived units and 10-40% by weight of comonomer-derived units from one or more C4-C20 α-olefins; a density in the range of 0.850 g / cc to 0.915 g / cc; and a density in the range of 0.1 dg / min to 1000 MI in the range of dg / min; MIR (I21.6 / I2.16) in the range of 18 to 100, and at least two TREF peaks, wherein at least one TREF peak is a major fraction accounting for at least 90% by weight of the ethylene copolymer, and wherein at least one TREF peak is a minor fraction accounting for less than 8% by weight of the ethylene copolymer and occurring in the range of 60°C to 95°C.

[0179] Implementation Scheme 12: The method of Implementation Scheme 11, wherein 5-45% by weight of the total amount of catalyst and activator is added to a conduit upstream of the solution polymerization reactor.

[0180] Implementation Scheme 13: The method of Implementation Scheme 11 or 12, wherein 5-45% by weight of the total amount of ethylene is added to a conduit upstream of the solution polymerization reactor.

[0181] Implementation Scheme 14: The method of any of Implementation Schemes 11 to 13, wherein 5-45% by weight of the total amount of comonomer is added to a conduit upstream of the solution polymerization reactor.

[0182] Implementation Scheme 15: The method of any of Implementation Schemes 11 to 14, wherein at least 90% by weight of the ethylene copolymer is prepared in a solution polymerization reactor, and the remainder of the ethylene copolymer is prepared in a conduit upstream of the solution polymerization reactor.

[0183] Implementation Scheme 16: A method for preparing copolymers by solution polymerization, comprising: (a) feeding ethylene, at least one comonomer, and a solvent into a solution polymerization reactor in a controlled proportion; (b) adding a single metallocene catalyst and an activator into the solution polymerization reactor; (c) polymerizing at least a portion of the ethylene and at least one other monomer in the solution polymerization reactor to produce an ethylene copolymer having at least 5% by weight of the comonomer; (d) effluent the ethylene prepolymer from the solution polymerization reactor; and (e) feeding additional ethylene into a downstream conduit of the solution polymerization reactor in a controlled proportion to provide an ethylene copolymer product comprising: at least 60% by weight of ethylene-derived units and 10-40% by weight of comonomer-derived units from one or more C4-C20 α-olefins; a density in the range of 0.850 g / cc to 0.915 g / cc; and a density in the range of 0.1 dg / min to 1000 g / min. MI in the range of dg / min; MIR (I21.6 / I2.16) in the range of 18 to 100, and at least two TREF peaks, wherein at least one TREF peak is a major fraction accounting for at least 90% by weight of the ethylene copolymer product, and wherein at least one TREF peak is a minor fraction accounting for less than 8% by weight of the ethylene copolymer product and occurring in the range of 60°C to 95°C.

[0184] Implementation Scheme 17: The method of Implementation Scheme 16, wherein 5-45% by weight of the total amount of catalyst and activator is added to a conduit downstream of the solution polymerization reactor.

[0185] Implementation Scheme 18: The method of Implementation Scheme 16 or 17, wherein 5-45% by weight of the total amount of ethylene is added to a conduit downstream of the solution polymerization reactor.

[0186] Implementation Scheme 19: The method of any of Implementation Schemes 16 to 18, wherein 5-45% by weight of the total amount of comonomer is added to a conduit downstream of the solution polymerization reactor.

[0187] Implementation Scheme 20: The method of any of Implementation Schemes 16 to 19, wherein at least 90% by weight of the ethylene copolymer is prepared in a solution polymerization reactor, and the remainder of the ethylene copolymer is prepared in a conduit downstream of the solution polymerization reactor.

[0188] All values ​​are indicated by “about” or “approximately” and take into account experimental errors and biases expected by those skilled in the art.

[0189] Based on the foregoing description, many changes, modifications and variations will be apparent to those skilled in the art without departing from the spirit or scope of this disclosure, and when lower and upper limits of numerical values ​​are listed herein, a range from any lower limit to any upper limit is contemplated.

[0190] The foregoing defines various terms. Where a term used in the claims is not defined above, it shall be given the broadest definition already provided to a person skilled in the art, as reflected in at least one printed publication or authorized patent. Furthermore, for all jurisdictions where such inclusion is permissible, all patents, test procedures, and other documents referenced in this application are fully incorporated by reference, provided that such disclosure does not contradict this application.

[0191] While the foregoing relates to embodiments of the invention, other and further embodiments of the invention may be devised without departing from the basic scope of the invention, the scope of which is defined by the appended claims.

Claims

1. An ethylene copolymer, comprising: At least 60% by weight of ethylene-derived units and 10-40% by weight of comonomer-derived units from one or more C4-C20 α-olefins, wherein the copolymer has: Density in the range of 0.850 g / cc to 0.915 g / cc; MI in the range of 0.1 dg / min to 1000 dg / min; MIR(I) in the range of 18 to 100 21.6 / I 2.16 ),and At least two TREF peaks, wherein at least one TREF peak is a major fraction comprising at least 90% by weight of the copolymer, and wherein at least one TREF peak is a minor fraction comprising less than 8% by weight of the copolymer and occurring in the range of 60°C to 95°C.

2. The ethylene copolymer according to claim 1, wherein the major fraction TREF peak appears in the range of 0°C to 80°C.

3. The ethylene copolymer of claim 1, wherein the copolymer is polymerized by solution polymerization using a plug flow reactor or CSTR, and the copolymer has a sludge concentration of 6% to 40% (polymer weight / solvent weight).

4. The ethylene copolymer according to claim 1, wherein the copolymer has a MWD (Mw / Mn) of 1.2-5.

0.

5. The ethylene copolymer of claim 1, wherein the copolymer has a branching index of 0.850-0.990 as measured by GPC-4D.

6. The ethylene copolymer of claim 1, wherein the copolymer is used in TPO, injection molding, elastic and film applications.

7. The ethylene copolymer of claim 1, wherein the copolymer is polymerized in a single reactor using a single metallocene catalyst system.

8. The ethylene copolymer of claim 1, wherein the copolymer further comprises one or more granule coating additives.

9. The ethylene copolymer of claim 1, wherein the copolymer does not contain any added metal stearate or siloxane.

10. The ethylene copolymer of claim 1, wherein the copolymer does not contain any added HDPE, LDPE or talc release agent.

11. A method for preparing copolymers by solution polymerization, comprising: (a) Ethylene, at least one comonomer and solvent are fed into a conduit upstream of the solution polymerization reactor in a controlled ratio; (b) Adding a single metallocene catalyst and activator into a conduit; (c) Polymerizing at least a portion of ethylene and at least one other monomer in a solution polymerization reactor to produce an ethylene prepolymer having at least 5% by weight of comonomer; (d) The ethylene prepolymer is fed into the solution polymerization reactor; (e) Adding additional ethylene, comonomers, catalysts, and activators in controlled proportions and optionally additional solvents to the solution polymerization reactor; and (f) Operating a solution polymerization reactor to produce an ethylene copolymer, the ethylene copolymer comprising: At least 60% by weight of ethylene-derived units and 10-40% by weight of comonomer-derived units from one or more C4-C20 α-olefins; Density in the range of 0.850 g / cc to 0.915 g / cc; MI in the range of 0.1 dg / min to 1000 dg / min; MIR(I) in the range of 18 to 100 21.6 / I 2.16 ),and At least two TREF peaks, wherein at least one TREF peak is a major fraction comprising at least 90% by weight of the ethylene copolymer, and at least one TREF peak is a minor fraction comprising less than 8% by weight of the ethylene copolymer and occurring in the range of 60°C to 95°C.

12. The method of claim 11, wherein 5-45% by weight of the total amount of catalyst and activator is added to the conduit upstream of the solution polymerization reactor.

13. The method of claim 11, wherein 5-45% by weight of the total amount of ethylene is added to the conduit upstream of the solution polymerization reactor.

14. The method of claim 11, wherein 5-45% by weight of the total amount of comonomer is added to the conduit upstream of the solution polymerization reactor.

15. The method of claim 11, wherein at least 90% by weight of the ethylene copolymer is prepared in a solution polymerization reactor, and the remainder of the ethylene copolymer is prepared in a conduit upstream of the solution polymerization reactor.

16. A method for preparing copolymers by solution polymerization, comprising: (a) Ethylene, at least one comonomer and solvent are fed into a solution polymerization reactor in a controlled ratio; (b) Adding a single metallocene catalyst and activator to a solution polymerization reactor; (c) Polymerizing at least a portion of ethylene and at least one other monomer in a solution polymerization reactor to produce an ethylene copolymer having at least 5% by weight of comonomer; (d) Allow the ethylene prepolymer to flow out of the solution polymerization reactor; (e) Adding additional ethylene in a controlled proportion to the ethylene copolymer in a downstream conduit of the solution polymerization reactor to provide an ethylene copolymer product comprising: At least 60% by weight of ethylene-derived units and 10-40% by weight of comonomer-derived units from one or more C4-C20 α-olefins; Density in the range of 0.850 g / cc to 0.915 g / cc; MI in the range of 0.1 dg / min to 1000 dg / min; MIR(I) in the range of 18 to 100 21.6 / I 2.16 ),and At least two TREF peaks, wherein at least one TREF peak is a major fraction comprising at least 90% by weight of the ethylene copolymer product, and wherein at least one TREF peak is a minor fraction comprising less than 8% by weight of the ethylene copolymer product and occurring in the range of 60°C to 95°C.

17. The method of claim 16, wherein 5-45% by weight of the total amount of catalyst and activator is added to a conduit downstream of the solution polymerization reactor.

18. The method of claim 16, wherein 5-45% by weight of the total amount of ethylene is added to a conduit downstream of the solution polymerization reactor.

19. The method of claim 16, wherein 5-45% by weight of the total amount of comonomer is added to a conduit downstream of the solution polymerization reactor.

20. The method of claim 16, wherein at least 90% by weight of the ethylene copolymer is prepared in a solution polymerization reactor, and the remainder of the ethylene copolymer is prepared in a conduit downstream of the solution polymerization reactor.

Images