Ethylene copolymers for photovoltaic cells

Abstract

An ethylene copolymer capable of producing films with excellent optical properties in the wavelength range of 280 to 1,100 nm, including moisture resistance, creep resistance, tensile strength, and tear strength. The ethylene copolymer is composed of at least 50% by weight of ethylene-derived units and at least 20% by weight of at least one C3-C20 comonomer, and has branching indices g'(Mz) and g'(Mz+1) along with tri-substituted olefins and reactivity ratios (r1r2) significantly different from other ethylene copolymers of similar density. The ethylene copolymer also exhibits significantly improved processability properties and high volume resistivity (>10 15 ohms x cm), making these copolymers particularly suitable for PV cell applications.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Application No. 63 / 377,365, filed September 28, 2022, the entire contents of which are incorporated herein by reference. Field FIELD OF THE INVENTION Embodiments of the present invention generally relate to ethylene copolymers and electronic device modules embodying such copolymers. More particularly, embodiments provided herein relate to ethylene copolymers suitable for photovoltaic cell applications. [Background technology]

[0002] Polyolefin plastomers, primarily copolymers of ethylene and butene or octene, are increasingly being used as polymer encapsulants for photovoltaic (PV) cell applications. These polymers are replacing ethylene vinyl acetate (EVA) copolymers, and studies have shown that plastomer-based encapsulants offer improved power generation over a 30-year service life compared to EVA. Plastomer films used as encapsulants offer higher barrier properties against potential-induced degradation (PID) and less power degradation compared to EVA films, both of which contribute to lower power loss. Discoloration due to yellowing and the evolution of acetic acid in EVA resins during service use leads to increased power loss in EVA film-based encapsulants. Polymer film encapsulants for PV cells must satisfy several functionalities. Electrical properties, as indicated by high volume resistivity, are useful for reducing power loss. Other important properties are often considered good optical properties, as measured by high light transmission in the wavelength range of 280-1100 nm; improved moisture barrier properties, as indicated by low water vapor transmission rate (WVTR); high crosslink density, which provides creep resistance; and good mechanical properties, as indicated by tensile strength, flexural modulus, and tear strength. The question that needs to be addressed is how to achieve all of these functionalities in a single polyolefin polymer.

[0003] Several patents disclose the use of plastomer resins as encapsulating materials for PV cells. For example, U.S. Patent No. 9,349,895 B2 and its counterpart, Chinese Patent No. 103189996 B, describe ethylene alpha-olefin copolymers suitable as PV cell encapsulants, having a density ranging from 0.865 to 0.884 g / cc, a MI(190°C) ranging from 2 to 10, and a Shore A hardness ranging from 60 to 85. U.S. Patent No. 8,581,094 B2 and its counterpart, Chinese Patent No. 101563786 B, describe PV cell devices having polyolefin copolymer encapsulants with a density less than 0.9 g / cc, a melting point less than 95°C, an alpha-olefin content ranging from 15 to 50% by mass, an SCBDI of at least 50, and optionally a free radical initiator and a co-crosslinking agent. Korean Patent No. 101191126 B1 describes an encapsulant sheet for solar cells, which sheet contains an ultra-low density ethylene-alpha-olefin copolymer (0.850-0.890 g / cc), a low-density ethylene-alpha-olefin copolymer (0.890-0.920 g / cc), and a silane-grafted ultra-low density copolymer. Korean Patent No. 101723708 B1 describes a polyolefin resin terpolymer used as an encapsulant, in which the polyolefin has a first crystallization temperature in the range of 45°C to 60°C and a second crystallization temperature lower than the first crystallization temperature of the resin.

[0004] U.S. Patent No. 8,329,848 B2 describes ethylene butene copolymers having a vinyl group content ranging from 0.06 to 1 per 1,000 C atoms, a density ranging from 0.850 to 0.910 g / cc, a MIR (I10 / I2.16) of less than 7.7, a MI ranging from 0.1 to 25 dg / min, and an ethylene content ranging from 80 to 95 mol%. U.S. Patent No. 10,774,205 B2 describes polymers having a multimodal composition distribution, each of which has a distinct crystallization peak at TREF ranging from 40°C to 110°C. However, there remains a need for new ethylene-based copolymers that can be made into films with excellent optical properties in the 200-900 nm wavelength range, good processability, moisture resistance, creep resistance, tensile strength, flexural modulus, and tear strength. Such films would be particularly well suited to address the needs of PV cell applications. Summary of the Invention

[0005] Provided herein are ethylene copolymers, electronic device modules, and methods for producing both. The ethylene copolymers comprise at least 50% by weight of ethylene-derived units and at least 20% by weight of at least one C3-C20 comonomer. The ethylene copolymers have a melt index, measured in accordance with ASTM D1238 (190°C / 2.16 kg), of 0.5 g / 10 min to about 50 g / 10 min, and a density, measured in accordance with ASTM D792, of about 0.860 g / cc to 0.880 g / cc. The copolymers have a first long-chain branching index (g'(Mz)) of 0.80 to 0.93, a second long-chain branching index (g'(Mz+1)) of 0.80 to 0.93, and a vinyl / total unsaturation of less than 0.7. The trisubstituted olefin has an unsaturation level of 50 to 500, and a volume resistivity at 23°C of 4 x 10. 15 Such ethylene copolymers can be produced using metallocene and post-metallocene catalysts in solution polymerization processes, as further provided herein.

[0006] These ethylene-based copolymers have significantly improved processability properties and high volume resistivity (>10 15 It has been surprisingly found that films can be made that have excellent optical properties (ohm×cm), moisture resistance, creep resistance, tensile strength, flexural modulus, and tear strength at wavelengths from 200 to 900 nm, making these copolymers particularly suitable for electronic device modules, such as PV cell applications.

[0007] So that the above-mentioned features of the present invention can be understood in detail, a more particular description of the invention briefly outlined above can be made by reference to embodiments, some of which are illustrated in the accompanying drawings. It should be noted, however, that the accompanying drawings illustrate merely typical embodiments of the invention, and since the invention is capable of other equally effective embodiments, the accompanying drawings should not therefore be considered as limiting its scope. [Brief explanation of the drawings]

[0008] [Figure 1A] FIG. 1 shows volume resistivity plotted against g′(Mz+1) / g′-average value for samples 1-6 and other commercially available ethylene copolymers of similar density. [Figure 1B] FIG. 1 shows volume resistivity plotted against g′(Mz+1) / g′-average value for samples 1-6 and other commercially available ethylene copolymers of similar density. [Figure 1C] FIG. 1 shows g′(Mz+1) / g′-average plotted against g′(Mz+1) values ​​by GPC for samples 1-6 and other commercially available ethylene copolymers of similar density. [Figure 2A] FIG. 1 shows trisubstituted olefins versus g′(Mz+1) determined from HNMR for samples 1-6 and other commercial ethylene copolymers of similar density. [Figure 2B] FIG. 1 shows tri-substituted olefins determined from HNMR versus g′(Mz) by GPC for samples 1-6 and other commercially available ethylene copolymers of similar density. [Figure 3] FIG. 1 shows vinyl / total unsaturation determined from HNMR versus g′(Mz) by GPC for samples 1-6 and other commercially available ethylene copolymers of similar density. [Figure 4A] FIG. 1 shows r1r2 values ​​versus g'(Mz+1) from NMR experiments for samples 1-6 and other commercial ethylene copolymers of similar density. [Figure 4B]FIG. 1 shows r1r2 values ​​versus g'Mz from NMR testing for samples 1-6 and other commercial ethylene copolymers of similar density. [Figure 5A] FIG. 1 shows the phase angle at a complex modulus of 10,000 Pa for Samples 1 to 6 and other commercially available ethylene copolymer grades. [Figure 5B] FIG. 1 shows the phase angle at a complex modulus of 50,000 Pa for samples 1-6 and other commercially available ethylene copolymer grades. [Figure 6] FIG. 1 shows both differential and cumulative TREF-IR data for samples 1-4. [Figure 7] FIG. 1 is a diagram comparing cooling cycle data for samples 1 to 4. [Figure 8] FIG. 1 is a diagram showing the water vapor transmission rate (WVTR) characteristics of Samples 1 to 4. [Figure 9] FIG. 1 shows the cure characteristics of single and dual reactor compositions for Samples 1-4. [Figure 10] FIG. 1 shows melt pressure and screw torque during extrusion at a melt temperature of 100° C. for 0.5 mm thick films made from Sample 2 and Sample 4, and two other comparative commercial polymers of similar density. DETAILED DESCRIPTION OF THE INVENTION

[0009] Provided are ethylene copolymers capable of producing films with excellent optical properties at wavelengths from 280 to 1,100 nm, including moisture resistance, creep resistance, tensile strength, and tear strength. The ethylene copolymers have branching indices g'(Mz) and g'(Mz+1) measured from GPC-4D, along with tri-substituted olefins and reactivity ratios (r1r2) determined using HNMR, that are significantly different from other ethylene copolymers of similar density. These ethylene copolymers provided herein also have significantly improved processability properties and high volume resistivities (>10 15 It has been surprisingly found that these copolymers, with a tensile strength of ohms x cm, are particularly suitable for electronic device modules, such as PV cell applications.

[0010] It should be understood that the disclosure provided herein provides several exemplary embodiments for implementing different features, structures, and / or functions of the present invention. While exemplary embodiments of components, arrangements, and configurations are described to simplify the disclosure, these exemplary embodiments are provided merely as examples and are not intended to limit the scope of the present invention. In addition, the present disclosure may repeat reference numerals and / or letters in various exemplary embodiments and throughout the figures provided herein. This repetition is for simplicity and clarity and does not, in itself, dictate a relationship between the various exemplary embodiments and / or configurations discussed in the figures. Furthermore, the exemplary embodiments presented herein may be combined in any combination, i.e., any element from one exemplary embodiment may be used in any other exemplary embodiment, without departing from the scope of the present disclosure.

[0011] Additionally, certain terms are used throughout the following description and claims to refer to particular components. As one skilled in the art will appreciate, various entities may refer to the same component by different names, and thus the naming conventions for elements described herein are not intended to limit the scope of the invention unless specifically defined herein. Furthermore, the naming conventions used herein are not intended to distinguish between components that differ in name but not function.

[0012] In the following discussion and claims, the terms "including" and "comprising" are intended to be open-ended and, therefore, should be interpreted to mean "including, but not limited to." The phrase "consisting essentially of" means that the described / claimed composition does not contain any other component that materially alters its properties by any amount greater than 5%, and in any case does not contain any other component to a level greater than 3% by weight.

[0013] The term "or" is intended to encompass both exclusive and inclusive cases, i.e., "A or B" is intended to be synonymous with "at least one of A and B," unless expressly specified otherwise herein. The indefinite articles "a" and "an" refer to both singular (i.e., "one") and plural (i.e., one or more) references unless the context clearly dictates otherwise. For example, embodiments using "an olefin" include embodiments in which one, two, or more olefins are used, unless specified to the contrary or unless the context clearly dictates that only one olefin is used.

[0014] The term "wt%" means weight percentage, "vol%" means volume percentage, "mol%" means mole percentage, "ppm" means parts per million, and "ppm by mass" and "wppm" are used interchangeably and mean parts per million by weight. All concentrations herein are expressed based on the total amount of the composition in question unless otherwise specified. The term "polymer" refers to any two or more identical or different repeat / mer units or units. The term "homopolymer" refers to a polymer having the same units. The term "copolymer" refers to a polymer having two or more units that are different from each other, including terpolymers, etc. The term "terpolymer" refers to a polymer having three units that are different from each other. The term "different" when referring to units indicates that the units differ from each other by at least one atom or are isomerically different. Similarly, as used herein, the definition of polymer includes homopolymers, copolymers, etc. By way of example, when a copolymer is said to have a "propylene" content of 10% to 30% by weight, it is understood that the repeat / mer units or simply units in the copolymer are derived from propylene in the polymerization reaction, and that the derived units are present in an amount of 10% to 30% by weight, based on the weight of the copolymer.

[0015] As used herein, "Mn" refers to the number-average molecular weight of different polymers in a polymeric material, "Mw" refers to the weight-average molecular weight of different polymers in a polymeric material, and "Mz" refers to the z-average molecular weight of different polymers in a 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 noted, all molecular weights (e.g., Mw, Mn, Mz) are reported in g / mol. The nomenclature of elements and their groups used herein conforms to the periodic table used by the International Union of Pure and Applied Chemistry since 1988. An example periodic table is shown on the inside cover page of Advanced Inorganic Chemistry, 6th Edition, by F. Albert Cotton et al. (John Wiley & Sons, Inc., 1999).

[0016] Considering ethylene copolymers in more detail, they can be of unimodal or bimodal composition and can be produced in a single reactor or dual reactors. Single-reactor ethylene copolymers can have a TREF elution temperature peak near 30°C. In the case of dual-reactor copolymers, the first reactor can produce a less crystalline component, typically with a TREF peak near 20°C, while the second reactor can produce a copolymer with a TREF peak above 40°C. Dual-reactor copolymers have a higher crystallization temperature (Tc) as determined by differential scanning calorimetry (DSC), lower WVTR, and improved tear strength compared to single-reactor products. The crystalline component contributes to a higher Tc, which improves pellet stability; provides a barrier to water ingress, reflected by lower WVTR properties; and improves crosslink density, all of which are essential for applications as polymer encapsulants in PV cells.

[0017] Ethylene copolymers contain ethylene and at least one other C3-C20 comonomer. Preferred ethylene copolymers are ethylene-butene and ethylene-octene plastomers. The ethylene content of the lower ethylene content fractions can range from a low of 55% to a high of 76% by weight. The ethylene content of the higher ethylene content fractions can range from a low of 60% to a high of 90% by weight. The ethylene content of the whole polymer can range from a low of 60% to a high of 85% by weight. The ethylene copolymers can have a melt index, measured according to ASTM D1238 (190°C / 2.16 kg), of 0.5 g / 10 min to about 50 g / 10 min. The melt index can also range from a low of about 0.5, 1.0, or 2.0 to a high of about 30, 40, or 50 g / 10 min. The melt index can also range from a low of about 0.5, 3.0, or 5.0 to a high of about 20, 35, or 45 g / 10 min.

[0018] Ethylene copolymers have a wide range of melt index ratios (MIR), i.e., MIR, measured according to ASTM D1238 (190°C / 2.16 kg), ranging from 20.0 to about 100.0. 21.6 / MI 2.16 The MIR can also range from a low of about 25, 30, or 40 to a high of about 60, 80, or 95. The ethylene copolymers can have a density of 0.850 g / cc to 0.920 g / cc, as measured according to ASTM D792, indicating that the ethylene copolymers can function as plastomers, possessing hybrid properties of elastomers and polymers. The ethylene copolymers can also have a density of about 0.860 g / cc to 0.880 g / cc. The density can range from a low of about 0.850, 0.855, 0.860, 0.865, or 0.870 to a high of about 0.874, 0.876, 0.880, 0.900, or 0.920 g / cc.

[0019] Ethylene copolymer is 8 x 1015 The volume resistivity at 23°C may be at least 8.5 x 10 Ωcm or more. 15 Ωcm, 9.5 x 10 15 Ωcm, 1×10 16 Ωcm, or 1.5 x 10 16 It can be Ωcm. The ethylene copolymers may have a ratio of g'Mz+1 to g'-average of 0.9 to 1.0, which may range from a low of 0.91, 0.92, or 0.93 to a high of 0.97, 0.98, or 0.99. The ethylene copolymers may have a vinyl / total unsaturation of less than 0.7 as estimated by H-NMR. The vinyl / total unsaturation may range from a low of about 0.01, 0.02, or 0.03 to a high of about 0.5, 0.6, or 0.7. The vinyl / total unsaturation may also range from a low of about 0.1, 0.2, or 0.3 to a high of about 0.5, 0.6, or 0.7.

[0020] The ethylene copolymers can have an unsaturation level of the trisubstituted olefin, as determined by H-NMR, of 50 to 500. The unsaturation level of the trisubstituted olefin can also range from about 50, 80, or 100 to as high as about 300, 400, or 500. The unsaturation level of the trisubstituted olefin can also range from about 60 to 480, 80 to 420, or 100 to 300. The ethylene copolymer may have a reactivity ratio of 0.8 or less. The reactivity ratio may range from 0.2 to 0.8. The reactivity ratio may range from a low of 0.2, 0.3, or 0.35 to a high of 0.5, 0.65, or 0.8. The reactivity ratio may be 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, or 0.8.

[0021] Polymerization Process Ethylene copolymers can be produced using a solution polymerization process. Preferably, the solution polymerization process is a bulk polymerization process, which refers to a polymerization process in which the monomers and / or comonomers to be polymerized are used as the solvent or diluent, with little or no inert solvent used as the liquid or diluent. A small portion of the inert solvent may be used as a carrier for the catalyst and scavenger. The term "solution polymerization" refers to a polymerization process in which a polymer is dissolved in a liquid polymerization medium, such as an inert solvent, a monomer, or a blend thereof. Solution polymerization is typically homogeneous, referring to a polymerization process in which the polymer product is dissolved in the polymerization medium. Such systems are preferably not turbid, as described in J. Vladimir Oliveira, C. Dariva, and JC Pinto, Ind. Eng. Chem. Res., 29, 2000, 4627. A homogeneous polymerization process is typically one in which at least 90% by weight of the product is soluble in the reaction medium.

[0022] Suitable solution polymerization processes for preparing the polymer blend compositions disclosed herein are generally described in more detail in U.S. Patent Nos. 9,359,535, 7,470,118, 7,226,553, and 7,033,152, which are incorporated herein by reference in their entireties. International Publication No. WO 2017 / 058385 describes a solution polymerization process using a single or multiple spiral heat exchanger system for the continuous polymerization of C2-C40 olefins, which may also be used and is incorporated herein by reference in its entirety. The ethylene copolymer may exhibit a low level of long chain branching (LCB). In particular, the ethylene copolymer may have a first long chain branching index (g'(Mz)) ranging from 0.30 to 1.00, preferably from 0.70 to 0.97. The first long chain branching index (g'(Mz)) may also range from 0.80 to 0.93. The first long chain branching index (g'(Mz)) may also range from a low value of 0.80, 0.82, or 0.85 to a high value of 0.90, 0.92, or 0.93. The first long chain branching index (g'(Mz)) may also be 0.80, 0.81, 0.82, 0.83, 0.84, 0.85, 0.86, 0.87, 0.88, 0.89, 0.90, 0.91, 0.92, or 0.93.

[0023] The ethylene copolymer may have a second long chain branching index (g'(Mz+1)) of 0.30 to 1.00, preferably 0.70 to 0.97. The second long chain branching index (g'(Mz+1)) may also range from 0.80 to 0.93. The second long chain branching index (g'(Mz+1)) may also range from a low of 0.80, 0.82, or 0.85 to a high of 0.90, 0.92, or 0.93. The second long chain branching index (g'(Mz+1)) may also be 0.80, 0.81, 0.82, 0.83, 0.84, 0.85, 0.86, 0.87, 0.88, 0.89, 0.90, 0.91, 0.92, or 0.93.

[0024] Comonomers The at least one other comonomer can comprise any one or more C4-C20 olefins. The C4-C20 comonomers can be linear, branched, or cyclic. Suitable C4-C20 cyclic olefins can be strained or unstrained, monocyclic or polycyclic, and may contain heteroatoms and / or one or more functional groups. The C2 concentration in the reactor can be in the range of 0.1 to 40.0 wt.%, and the comonomer concentration in the reactor can be in the range of 0.1 to 40.0 wt.%. Specific examples of comonomers include butene, pentene, hexene, heptene, octene, nonene, decene, undecene, dodecene, norbornene, norbornadiene, dicyclopentadiene, cyclopentene, cycloheptene, cyclooctene, cyclooctadiene, cyclododecene, 7-oxanorbornene, 7-oxanorbornadiene, substituted derivatives thereof, and isomers thereof, preferably hexene, heptene, 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 homologs and derivatives, preferably norbornene, norbornadiene, and dicyclopentadiene.

[0025] In preferred embodiments, one or more dienes (diolefin comonomers) are added to the polymerization process. The diene may be present in the polymers made herein at up to 10 wt. %, preferably 0.00001 to 8.0 wt. %, preferably 0.002 to 8.0 wt. %, and even more preferably 0.003 to 8.0 wt. %, based on the total weight of the composition. In some embodiments, 500 ppm or less, preferably 400 ppm or less, and preferably 300 ppm or less of diene is added to the polymerization. In other embodiments, at least 50 ppm, or 100 ppm or more, or 150 ppm or more of diene is added to the polymerization.

[0026] Suitable diolefin comonomers include any hydrocarbon structure, preferably C4-C30, having at least two unsaturated bonds, at least one of which is readily incorporated into the polymer chain during chain growth. It is further preferred that the diolefin comonomer be selected from alpha, omega-diene monomers (i.e., divinyl monomers). More preferably, the diolefin comonomer is a linear divinyl monomer, most preferably one containing from 4 to 30 carbon atoms. Specific examples of preferred dienes include butadiene, pentadiene, hexadiene, heptadiene, octadiene, nonadiene, decadiene, undecadiene, dodecadiene, tridecadiene, tetradecadiene, pentadecadiene, hexadecadiene, heptadecadiene, octadecadiene, nonadecadiene, icosadiene, heneicosadiene, docosadiene, tricosadiene, tetracosadiene, pentadiene, hexadiene, heptadecadiene, octadecadiene, nonadecadiene, icosadiene, heneicosadiene, docosadiene, tricosadiene, tetracosadiene, pentadecadiene ... hexadiene, hexadiene, octadiene, hexadiene, hexadiene, hexadiene, octadiene, hexadiene, hexadiene, hexadiene, hexadiene, hexadiene, hexadiene, hexadiene, hexadiene, hexadiene, hexa Particularly preferred dienes include 1,6-heptadiene, 1,7-octadiene, 1,8-nonadiene, 1,9-decadiene, 1,10-undecadiene, 1,11-dodecadiene, 1,12-tridecadiene, 1,13-tetradecadiene, and low molecular weight polybutadienes (Mw less than 1000 g / mol). Preferred cyclic dienes include cyclopentadiene, 5-vinyl-2-norbornene, norbornadiene, 5-ethylidene-2-norbornene, divinylbenzene, and dicyclopentadiene, or higher ring-containing diolefins with or without substituents at various ring positions.

[0027] catalyst system Suitable catalyst systems for producing the ethylene copolymers provided herein can include one or more bridged metallocene compounds having a single substituted carbon or silicon atom bridging two auxiliary monoanionic ligands of the metallocene metal center, e.g., substituted or unsubstituted cyclopentadienyl-containing (Cp) ligands and / or substituted and unsubstituted Group 13-16 heteroatom ligands. The bridging substituents can be substituted aryl groups, and the substituents include at least one solubilizing hydrocarbylsilyl substituent located on at least one of the aryl group bridging substituents. The substituents present on the cyclopentadienyl and / or heteroatom ligands can be C1-C2 alkyl groups, replacing one or more of the hydrogen groups on those ligands or one or more of the hydrogen groups on the fused aromatic rings on the cyclopentadienyl ring. 30 The aromatic ring may contain a hydrocarbyl, hydrocarbylsilyl, or hydrofluorocarbyl group. The aromatic ring may be a substituent on a cyclopentadienyl ligand, including indenyl and fluorenyl derivatives of the cyclopentadienyl group and their hydrogenated counterparts. Such aromatic rings typically contain one or more aromatic ring substituents selected from linear, branched, cyclic, aliphatic, aromatic, or complex structural groups, including fused or pendant rings. Examples include methyl, isopropyl, n-propyl, n-butyl, isobutyl, tertiary butyl, neopentyl, phenyl, n-hexyl, cyclohexyl, benzyl, and adamantyl. As used herein, the term "hydrocarbon" or "hydrocarbyl" is intended to include compounds or groups that are essentially hydrocarbon in character but may contain up to about 10 mol% of non-carbon heteroatoms, such as boron, silicon, oxygen, nitrogen, sulfur, and phosphorus. In addition, this term is intended to include hydrofluorocarbyl substituents. "Hydrocarbylsilyl" is exemplified by, but not limited to, dihydrocarbyl- and trihydrocarbylsilyl, and preferred hydrocarbyl groups are C-C relative to the bridging group phenyl. 30The substituent is hydrocarbyl, hydrocarbylsilyl, or hydrofluorocarbyl substituent.For heteroatom-containing catalysts, refer to International Publication No. WO92 / 00333.In addition, the use of heteroatom-containing rings or fused rings, where non-carbon group 13, 14, 15, or 16 atom replaces one of ring carbons, is considered to be within the scope of the terms " cyclopentadienyl ", " indenyl ", and " fluorenyl " herein.For example, refer to the background and teachings of International Publication No. WO98 / 37106 and WO98 / 41530, which are incorporated herein by reference.

[0028] Particularly preferred cyclopentadienyl-based complexes are compounds, isomers, or mixtures of (para-trimethylsilylphenyl)(para-n-butylphenyl)methylene(fluorenyl)(cyclopentadienyl)hafnium dimethyl, di(para-trimethylsilylphenyl)methylene(2,7-di-tertbutylfluorenyl)(cyclopentadienyl)hafnium dimethyl, di(para-triethylsilylphenyl)methylene(2,7-di-tertbutylfluorenyl)(cyclopentadienyl)hafnium dimethyl, (para-triethylsilylphenyl)(para-t-butylphenyl)methylene(2,7-di-tertbutylfluorenyl)(cyclopentadienyl)hafnium dimethyl or dibenzyl, and di(para-triethylsilylphenyl)methylene(2,7-dimethylfluorenyl)(cyclopentadienyl)hafnium dimethyl or dibenzyl. Other suitable cyclopentadienyl-based complexes are described in International Publication No. WO / 2000 / 024793, which is also incorporated herein by reference.

[0029] activator The bridged metallocene compound can be activated for polymerization catalysis in any manner sufficient to permit coordination or cationic polymerization. This can be achieved for coordination polymerization when one ligand is abstractable and another is similarly abstractable for replacement with a ligand, such as an alkyl, silyl, or hydride, that permits insertion of an unsaturated monomer (labile ligand). Traditional activators for coordination polymerization techniques are, for example, suitable Lewis acids, such as alumoxane compounds, and ionizing anion precursor compounds that ionize the bridged metallocene metal center to a cation and abstract one to provide the matching non-coordinating anion.

[0030] For example, a suitable activator may include a cationic moiety. In all embodiments, the cationic moiety may be of the formula [R 1 R 2 R 3 AH] + wherein A is nitrogen and R 1 and R 2 Together - (CH2) a - group, a is 3, 4, 5, or 6, and together with the nitrogen atom forms a 4-, 5-, 6-, or 7-membered non-aromatic ring to which one or more aromatic or heteroaromatic rings are optionally fused via adjacent ring carbon atoms; R 3 is C1, C2, C3, C4, or C5 alkyl, or N-methylpyrrolidinium or N-methylpiperidinium. Alternatively, in any embodiment, the cationic moiety has the formula [R n AH4_ n ] + where A is nitrogen, n is 2 or 3, and all R are the same and are C1-C3 alkyl groups, such as trimethylammonium, trimethylanilinium, triethylammonium, dimethylanilinium, and dimethylammonium.

[0031] Suitable activators may be or include an anionic moiety [Y]. The anionic moiety may be of the formula [B(R4 )4] - where R 4 is an aryl group or a substituted aryl group, in which one or more substituents, the same or different, are selected from the group consisting of alkyl, aryl, halogen atoms, halogenated aryl, and haloalkylaryl groups. The substituents can be perhalogenated or perfluorinated aryl groups, including perfluorophenyl, perfluoronaphthyl, and perfluorobiphenyl. The cation and anion components of the catalyst systems disclosed herein can combine to form an activator compound. In all embodiments, the activator can be N,N-dimethylanilinium-tetra(perfluorophenyl)borate, N,N-dimethylanilinium-tetra(perfluoronaphthyl)borate, N,N-dimethylanilinium-tetrakis(perfluorobiphenyl)borate, N,N-dimethylanilinium-tetrakis(3,5-bis(trifluoromethyl)phenyl)borate, triphenylcarbenium-tetra(perfluorophenyl)borate, triphenylcarbenium-tetra(perfluoronaphthyl)borate, triphenylcarbenium-tetrakis(perfluorobiphenyl)borate, and / or triphenylcarbenium-tetrakis(3,5-bis(trifluoromethyl)phenyl)borate.

[0032] A particularly advantageous activator is dimethylanilinium tetrakis(heptafluoronaphthyl)borate. For detailed descriptions of suitable catalyst systems and activators, see also International Publication Nos. WO / 2021 / 162748, WO / 2013 / 134038, and WO / 2000 / 024793, each of which is incorporated herein by reference. As described above, a suitable polymerization process uses a polymerization catalyst system, particularly a polymerization catalyst system comprising at least one activator, at least one support, and at least one catalyst composition. 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. It is believed that the high volume resistivity of the ethylene copolymers provided herein can be achieved or enhanced by the specific catalyst system used to polymerize the copolymer. In photovoltaic cells, a viable method for mitigating potential-induced degradation (PID) is to prevent the flow of ionic current through the encapsulant. Volume resistivity is an intrinsic property of encapsulant polymer materials and is characterized by how strongly a given material resists the flow of electric current.

[0033] In a given catalyst system, the activator cations may remain in the polymer composition after activating the catalyst. As a result, the cations and anions may affect the electrical conductivity of the polymer. Because not all ions diffuse equally, different ions affect the polymer composition differently. In particular, the size of the ion, the charge of the ion, the interaction of the ion with the surrounding medium, and the dissociation energy of the ion with available counterions all affect the ability of the ion to diffuse through the surrounding medium, e.g., the polymer material. Conventional olefin polymerization activators contain weakly or non-coordinating anions. Weak coordination of the anions has been shown to lead to improved catalytic efficiency of cationic catalysts. However, the non-nucleophilic nature of non-coordinating anions also increases diffusion, so residual activator anions in the resulting polymer decrease the electrical resistivity of the polymer, thereby increasing electrical losses and reducing the insulating ability of the resulting polymer.

[0034] It has been unexpectedly discovered that the volume resistivity of ethylene-based copolymers can be improved (increased) by reducing the level of residual ions and achieving a low ion diffusion rate. The transition metal bis(phenolate) complexes according to formula (I) shown and described in U.S. Pat. No. 11,225,539 have the ability to produce ethylene copolymers with high catalytic activity (approximately three times higher than conventional bridged metallocene compounds, such as those mentioned in paragraph

[0055] ). High catalytic activity leads to fewer residual ions in the polymer. Particularly suitable catalysts include dimethylzirconium [2',2'''-(pyridine-2,6-diyl)bis(3-adamantan-1-yl)-5-(tert-butyl)-[1,1'-biphenyl]-2-olate)] (Cat-Zr) or dimethylhafnium [2',2'''-(pyridine-2,6-diyl)bis(3-adamantan-1-yl)-5-(tert-butyl)-[1,1'-biphenyl]-2-olate)] (Cat-Hf). It has also been unexpectedly discovered that bulky activators, such as those compatible with the aforementioned Cat-Zr and Cat-Hf catalysts, slow the rate of ion diffusion during the polymerization process. Such activators include N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate (DMAH-BF20) or dimethylanilinium tetrakis(heptafluoronaphthyl)borate (DMAH-BF28).

[0035] Ethylene copolymers have the following properties: a. >8×10 15 Volume resistivity at 23°C in Ωcm, b. g'Mz+1(branch)<0.931, g'Mz+1 / g'-avg<1, c. g'Mz(branching)<0.93 and g'Mz+1(branching)<0.93, with significantly higher trisubstituted olefins; d. g'Mz<0.94 and vinyl / total unsaturation <0.2; e. Any g'Mz<0.94 with a reactivity ratio ≤ 0.7, and / or f. Lower r1r2 values ​​than the comparative copolymers (mostly >1, maximum about 1.5), indicating a lower level of chain blockiness, as seen in Figure 4. The unique combination of These unique attributes distinguish the ethylene copolymers provided herein from other comparative ethylene copolymers. [Example]

[0036] The foregoing discussion can be further illustrated with reference to the following non-limiting examples. Six different ethylene copolymers were prepared. Samples 1-4 were ethylene-butene copolymers, and Samples 5-6 were ethylene-octene copolymers. All six copolymers were made in a pilot-size solution reactor using di(para-triethylsilylphenyl)methylene(2,7-di-tertbutyl-fluorenyl)(cyclopentadienyl)hafnium dimethyl as the catalyst and dimethylanilinium tetrakis(heptafluoronaphthyl)borate as the cocatalyst, both available from ExxonMobil Product Solutions Company. Tables 1 and 2 provide more information about each reactor component and the copolymer as a whole for Samples 1-6. Tables 3 and 4 provide similar information for comparative commercial copolymers. Table 5 reports the tensile strength and flexural modulus of compression molded samples of Samples 1-4.

[0037] [Table 1]

[0038] [Table 2]

[0039] [Table 3]

[0040] [Table 4]

[0041] [Table 5]

[0042] Figure 1A shows the volume resistivity plotted against the g'Mz+1 values ​​for Samples 1-6 and other commercially available ethylene copolymers of similar density, and Figure 1B shows the volume resistivity plotted against the g'(Mz+1) / g'-average value. Figure 1C shows the g'(Mz+1) / g'-average plotted against the g'(Mz+1) values ​​by GPC for the same copolymers. As shown in Figures 1A-1C, for both the inventive and comparative commercially available copolymers, the volume resistivity at 23°C is >4 x 10 Ω cm, and g'Mz+1 (branching) <0.93, with g'Mz+1 / g'-average <1. Figure 2A shows the tri-substituted olefins versus g'(Mz+1) determined from HNMR, and Figure 2B shows the tri-substituted olefins versus g'(Mz) determined from HNMR for Samples 1-6 and other commercial ethylene copolymers of similar density. As shown in Figures 2A and 2B, Samples 1-6 exhibited significantly higher tri-substituted olefins, with g'Mz(branching)<0.93 and g'Mz+1(branching)<0.93.

[0043] Figure 3 shows the vinyl / total unsaturation as determined from HNMR versus g'(Mz) by GPC for samples 1-6 and other commercially available ethylene copolymers of similar density. Figure 3 shows that the resins of the present invention have g'Mz<0.94 and vinyl / total unsaturation values ​​of <0.2. Figure 4A shows the r1r2 values ​​versus g'(Mz+1) from NMR experiments for Samples 1-6 and other commercially available ethylene copolymers of similar density, and Figure 4B shows the r1r2 values ​​versus g'Mz from NMR experiments. The reactivity ratios of the copolymers of the present invention were ≦0.7 with all g'Mz<0.94, and had much lower r1r2 values ​​than the comparative copolymers (mostly >1, up to about 1.5), indicating lower levels of chain blockiness.

[0044] Figure 5A shows the phase angle at a complex modulus of 10,000 Pa, and Figure 5B shows the phase angle at a complex modulus of 50,000 Pa, for Samples 1-6 and other commercially available ethylene copolymer grades. As shown, the phase angles at complex moduli of 10,000 Pa and 50,000 Pa measured at ~5 MI and ~14 MI are significantly lower than the comparative examples at similar MI. Figure 6 shows both differential and cumulative TREF-IR data for Samples 1-4. The TREF data includes a soluble fraction below 0°C and an insoluble fraction with distinct elution temperatures. Samples 1 and 3 had one distinct peak elution temperature near 30°C. Samples 3 and 4 had two peak elution temperatures corresponding to the densities of the components in each reactor. The elution peak for the lower density component occurred near 20°C, while the elution peak for the higher density fraction was between 45 and 50°C.

[0045] Figure 7 compares the cooling cycle data for Samples 1-4. The peak crystallization temperature and corresponding heat of crystallization are plotted for each sample. A higher Tc was observed when comparing Sample 3 to Sample 1 (56 °C vs. 45 °C), as was the case when comparing Sample 4 to Sample 2 (61 °C vs. 49 °C). The heat of crystallization was lower for Sample 3 compared to Sample 1 (32 J / g vs. 34 J / g) and higher for Sample 4 vs. Sample 2 (36 J / g vs. 33 J / g). The increased Tc due to the higher crystallinity of the second reactor component was particularly important for maintaining stable pellets at lower polymer densities. Figure 7 also shows that the dual-reactor Sample 4 sample had a higher modulus. Figure 8 shows the water vapor transmission rate (WVTR) properties of Samples 1-4. Permeability, expressed in units of g / m² x day, is typically considered. Lower values ​​indicate improved barrier properties against water penetration. Samples 3 and 4 both have lower WVTR values ​​compared to their single-reactor analogs, Samples 1 and 3, respectively. The lower WVTR values ​​of the dual-reactor grades can be attributed to the higher crystalline fraction of the second reactor component.

[0046] Samples 1-4 were compounded with peroxide (Luperox 101) at 2.5 phr. The peroxide was added to the polymer in a Brabender Plasticorder using a batch size of 270 gm. The melt temperature of the Brabender was maintained at 70°C to mitigate premature crosslinking. The samples were added to the Brabender with the rotor running at 50 rpm until the polymer flowed and became homogenous within the cavity. The peroxide was added to the polymer, and the mixture was compounded for an additional 3 minutes before being discharged from the chamber. The curing characteristics of the samples were tested using an oscillating disc rheometer (ODR) at 180°C, 3-degree arc, and 30 minutes. The curing state was determined by the difference between the maximum torque value (MH) and the minimum torque value (ML), MH-ML, and the maximum curing rate was [(MH-ML) × 0.9-2] / (Tc 90 -Ts2), where Tc90 is the time to achieve 90% of the maximum HF and Ts2 is the setting time to a 2 torque unit increase.

[0047] Figure 9 shows the ODR parameters (cure rate and state of cure) comparing the single reactor samples (Samples 1 and 2) with their corresponding dual reactor analogs, Samples 3 and 4. Both the maximum cure rate and state of cure are higher for the dual reactor polymers compared to the single reactor candidates. Samples 2 and 4 (14 MI) were extruded in a sheet extruder at a melt temperature of 100°C to form 0.5 mm thick films. Figure 10 shows the melt pressure and screw torque during extrusion at a melt temperature of 100°C for 0.5 mm thick films made from Samples 2 and 4 and two other comparative commercial polymers of similar density. These copolymer samples exhibited lower torque than the commercial reference copolymer, indicating better processability in this particular application. It was further discovered that tailoring the individual molecular weights provided advantages over single-reactor polymers made at a fixed MI, particularly in processability during film extrusion.

[0048] Test Procedure In the foregoing examples, the following test methods and procedures were used. The density was measured according to ASTM D792, and the MI and MIR values ​​(MI 21.6 / MI 2.16 ) was measured according to ASTM D1238 (190°C / 2.16 kg). Molecular weight distributions and moments (Mw, Mn, Mz, Mw / Mn, Mz / Mn, etc.), comonomer content (C8), and long-chain branching index (g') were determined using high-temperature gel permeation chromatography (Polymer Char GPC-IR) equipped with a multichannel band filter-based infrared detector IR5, an 18-angle light scattering detector, and a viscometer. Three Agilent Plgel 10 μm Mixed-B LS columns were used for polymer separation. Detailed analytical principles and methods for molecular weight determination are described in paragraphs

[0044] to

[0051] of International Publication No. WO / 2019 / 246069, which is incorporated herein by reference. (Note that for the concentration I at each point in the chromatogram, the formula for c mentioned in paragraph

[0044] is c = βI, where β is the mass constant and I is the baseline-subtracted IR5 broadband signal intensity (I).) Unless otherwise specified, all molecular weight moments used or referred to in this disclosure are determined according to conventional molecular weight (IR molecular weight) determination methods (e.g., those referenced in paragraphs

[0044] to

[0045] of the immediately preceding International Publication), where it is noted that in the formula of such paragraph

[0044] , a = 0.695 and K = 0.000579 (1 - 0.75 Wt) are used, where Wt is the mass fraction of hexane comonomer, and it is further noted that the comonomer composition is determined by the ratio of the IR detector intensities corresponding to the CH2 and CH3 channels, calibrated using a series of PE and PP homo / copolymer standards whose nominal values ​​have been previously determined by NMR or FTIR (providing methyls per 1000 total carbons (CH3 / 1000TC) as described in paragraph

[0045] of the immediately preceding International Publication).

[0049] The TREF technique is performed as described in Wild, et al., J. Poly. Sci., Poly. Phys. Ed., Vol. 20, pg. 441 (1982) and U.S. Pat. No. 5,008,204, which are incorporated herein by reference. The SDBI measures the width of the solubility distribution curve for a given polymer. The procedure used herein for calculating the SDBI is described in International Publication No. WO 93 / 03093 (pp. 16-18), which is incorporated herein by reference.

[0050] The long-chain branching index (g') was measured using GPC-4D. A typical GPC-4D profile has Log M vs. g', which is used to estimate the g' average based on the average across molecular weights. The branching index g' average value ranges from 1 to 0, with 1 being linear (unbranched) and 0 being fully branched. Because the g' average does not clearly distinguish between branching changes at low levels (0.85 to 1), g'(Mz) and g'(Mz+1) were estimated at the higher molecular weight moments (Mz, Mz+1). The branching index g'(Mz) is the g' from the GPC-4D profile estimated at the z-average (third moment) molecular weight average. This calculation is performed by curve-fitting the g' vs. molecular weight data to an nth-order polynomial using a MATLAB program. The value of n is typically 3 to 4. The Mz value obtained from the GPC-IR measurement is inserted into the curve fit to calculate the g' associated with that molecular weight.

[0051] for C2% and r1r2 13 C NMR The sample was dissolved in deuterated 1,1,2,2-tetrachloroethane-d2 (tce-d2) at a concentration of 67 mg / mL at 140 °C. Spectra were recorded at 120 °C using a 600 MHz Bruker NMR spectrometer with a 10 mm CryoProbe. 13C NMR measurements used a 90° pulse, a 10 s delay, a transient response of 512, and gated decoupling. The polymer resonance peaks were referenced to the main polyethylene peak at 29.98 ppm.

[0052] Chemical shift assignments for ethylene-octene copolymers are described by Randall in "A Review Of High Resolution Liquid Carbon Nuclear Magnetic Resonance Characterization of Ethylene-Based Polymers", Polymer Reviews, 29:2, 201-5 317 (1989). Copolymer content, mole and mass %, triad sequence, and two-component calculations are also calculated and described in this paper using the methods established by Randall. The reactivity ratio (r1r2) is calculated as follows: r1r2=4×[EE]×[OO] / [EO] 2 where [EE], [EO], and [OO] are the binary molar concentrations, E is ethylene, and O is octene.

[0053] The reactivity product r1r2 is more fully described in Textbook of Polymer Chemistry, F.W. Billmeyer, Jr., Interscience Publishers, New York, p. 221 et seq. (1957). The reactivity product r1r2, where r1 is the reactivity of ethylene and r2 is the reactivity of propylene, can be calculated from the measured binary distributions (OO, EE, EO, and OE in this nomenclature) by applying the following formula: r1r2=4(EE)(OO) / (EO) 2 r1=K 11 / K 12 =[2(EE) / EO]X r2=K 22 / K 21 =[2(PP) / (EO)]X O=(OO)+(EO / 2) E = (EE) + (EO / 2) where Mol %E = [(E) / (E+O)] x 100 and X = E / O in the reactor; K 11 and K. 12 is the kinetic insertion constant of ethylene, K 21and K. 22 is the kinetic insertion constant of propylene.

[0054] As known to those skilled in the art, a reactivity product r1r2 of zero (0) can define an "alternating" copolymer, while a reactivity product of one is said to define a "statistically random" copolymer. In other words, copolymers with a reactivity product r1r2 between 0.6 and 1.5 are generally said to be random (in strict theoretical terms, only copolymers with a reactivity product r1r2 greater than 1.5 generally contain relatively long homopolymer sequences and are said to be "blocky"). 1 H NMR data were collected at 120 °C using a Bruker spectrometer and a 10 mm CryoProbe with an H frequency of at least 600 MHz. Data were recorded using a maximum pulse width of 45°, 5 seconds between pulses, and signal averaging of 512 transient responses. Samples were prepared by dissolving 80-100 mg of sample in 3 mL of solvent heated to 140 °C. For purposes of this invention and the claims thereto, unsaturation in polymers is defined as follows: Macromolecules, 2014, 47, 3782; Macromolecules, 2005, 38, 6988. 1 Determined by H NMR, but in case of conflict, Macromolecules, 2014, 47, 3782 shall control. Peak assignments are determined by reference to a solvent of 1,1,2,2-tetrachloroethane-d2 at 5.98 ppm. U.S. Patent Application Publication No. 2018162973 provides additional details, which are incorporated herein by reference.

[0055] Volume resistivity (VR) was tested according to the ExxonMobil method based on ASTM D257. Measurements were performed using a Keithley 6517B electrometer and a Keithley 8009 test fixture. Leakage current was measured directly on the instrument, and volume resistivity was calculated using the following formula:

number

[0056] Differential scanning calorimetry (DSC) was performed using a Perkin Elmer instrument with 5 mg to 10 mg samples, with two melting cycles and one cooling cycle between -80 °C and 200 °C at a rate of 10 °C / min. Melting temperatures (Tm) and crystallization temperatures (Tc) are reported in °C. Small-angle oscillatory shear (SAOS) measurements were performed at 190 °C with shear rates ranging from 0.01 s to 500 s. The phase angle (δ) was calculated as the constant modulus (G * A van Gurp-Palmen plot was performed by plotting the phase angle at complex moduli of 10,000 Pa and 50,000 Pa as a function of the modulus.

[0057] Water vapor transmission rate (WVTR, g / m) of compression-molded film 2 An internal method was used to estimate the solubility (days). A MOCON Permatran W-700 was used for the measurements. The test was performed at 37.8°C, atmospheric pressure of 760 mmHg, and relative humidity of 100%. 2 - WVTR values ​​reported in days are reported in metric perms (gm.mil / m 2 -day) permeance. The ethylene copolymers provided herein are particularly suitable for use in the manufacture of solar cells (also known as photovoltaic cells), photovoltaic (PV) modules, and other low-current electronic devices or modules, such as liquid crystal panels, electroluminescent devices, and plasma display units. Solar cell modules typically have one or more cells made from silicon, gallium-arsenide, and copper-iridium-selenium, along with a transparent protective material on top and a protective substrate material on the bottom, with the solar cells and protective material secured in place by the use of an encapsulant. The ethylene copolymers provided herein can be used as the top protective material, the bottom protective material, or both. The ethylene copolymers can provide films with excellent flexibility, transparency, and heat resistance, making the films particularly suitable for use in PV modules.

[0058] Ethylene copolymers can also be used in packaging. Modules such as those described above often utilize electronic devices in combination with one or more substrates that provide protection and / or support for their manufacture, transportation, and use. For example, devices of this type are often placed behind one or more glass cover sheets and / or between two substrates, one or both of which are made of glass, metal, plastic, rubber, or other materials. In such cases, ethylene copolymers can be used as an encapsulant or sealant for the devices within the module, or directly as a coating or skin layer for the module, depending on the module design, such as the backskin of a solar cell module.

[0059] List of Embodiments The present disclosure may further include any one or more of the following non-limiting embodiments. Embodiment 1. An ethylene copolymer comprising at least 50% by weight of ethylene-derived units and at least 20% by weight of at least one C3-C20 comonomer, the ethylene copolymer having a melt index, measured in accordance with ASTM D1238 (190°C / 2.16 kg), of 0.5 g / 10 min to about 50 g / 10 min, a density, measured in accordance with ASTM D792, of about 0.860 g / cc to 0.880 g / cc, a first long chain branching index (g'(Mz)) of 0.80 to 0.93, a second long chain branching index (g'(Mz+1)) of 0.80 to 0.93, a vinyl / total unsaturation of less than 0.7, an unsaturation level of trisubstituted olefins of 50 to 500; and a volume resistivity at 23°C of 4 x 1015 Ω cm or greater. Embodiment 2. The ethylene copolymer of embodiment 1, further comprising a ratio of g'Mz+1 / g'-average from 0.9 to 1.0. Embodiment 3. The ethylene copolymer of embodiment 1 or 2 having a vinyl / total unsaturation of less than 0.6.

[0060] Embodiment 4. The ethylene copolymer of any one of embodiments 1-3, wherein the trisubstituted olefin has an unsaturation level of from 60 to 450. Embodiment 5. The ethylene copolymer of any one of embodiments 1-4, comprising two or more TREF elution temperature peaks. Embodiment 6. The ethylene copolymer of any of embodiments 1-5, further comprising a first peak elution temperature less than 30°C and a second peak elution temperature greater than 40°C.

[0061] Embodiment 7. The ethylene copolymer of any one of embodiments 1-6, further comprising an r1r2 reactivity ratio of 0.8 or less. Embodiment 8. The ethylene copolymer of any one of embodiments 1 to 7, further comprising an r1r2 reactivity ratio of 0.2 to 0.8. Embodiment 9. The ethylene copolymer of any of embodiments 1-8, further comprising less than 10% by weight of diene-derived units. Embodiment 10. The ethylene copolymer of any of embodiments 1-9, wherein the at least one C3-C20 comonomer is butene or octene, or a combination thereof.

[0062] Embodiment 11. 1. An electronic device module comprising: at least one electronic device; and an ethylene copolymer film in direct contact with at least one surface of the electronic device; wherein the ethylene copolymer comprises at least 50% by weight of ethylene-derived units and at least 20% by weight of at least one C3-C20 comonomer; and wherein the copolymer has a melt index, measured in accordance with ASTM D1238 (190°C / 2.16 kg), of 0.5 g / 10 min to about 50 g / 10 min; a density, measured in accordance with ASTM D792, of about 0.860 g / cc to 0.880 g / cc; a first long-chain branching index (g'(Mz)) of 0.80 to 0.93; a second long-chain branching index (g'(Mz+1)) of 0.80 to 0.93; a vinyl / total unsaturation level of less than 0.7; an unsaturation level of trisubstituted olefins of 50 to 500; and a volume resistivity at 23°C of 4 x 1015 Ω cm or greater. Embodiment 12. The electronic device module of embodiment 11, wherein the copolymer further comprises a ratio of g'Mz+1 / g'-average from 0.9 to 1.0. Embodiment 13. The electronic device module of embodiment 11 or 12, wherein the copolymer further comprises a first peak elution temperature less than 30°C and a second peak elution temperature greater than 40°C.

[0063] Embodiment 14. The electronic device module of any of embodiments 11-13, wherein the copolymer further comprises an r1r2 reactivity ratio of 0.2 to 0.8. Embodiment 15. The electronic device module of any of embodiments 11-14, wherein the copolymer further comprises less than 10% by weight of diene-derived units, and the at least one C3-C20 comonomer is butene or octene, or a combination thereof. Embodiment 16. 1. A method for manufacturing an electronic device module, the method comprising: providing at least one electronic device; and laminating an ethylene copolymer film to at least one surface of the electronic device, wherein the ethylene copolymer comprises at least 50% by weight of ethylene-derived units and at least 20% by weight of at least one C3-C20 comonomer, and the copolymer has a melt index, measured in accordance with ASTM D1238 (190°C / 2.16 kg), of 0.5 g / 10 min to about 50 g / 10 min; a density, measured in accordance with ASTM D792, of about 0.860 g / cc to 0.880 g / cc; a first long-chain branching index (g'(Mz)) of 0.80 to 0.93; a second long-chain branching index (g'(Mz+1)) of 0.80 to 0.93; a vinyl / total unsaturation of less than 0.7; an unsaturation level of trisubstituted olefins of 50 to 500; and a volume resistivity at 23°C of 4 x 1015 Ω cm or greater.

[0064] Embodiment 17. The method of claim 16, wherein the copolymer further comprises a ratio of g'Mz+1 / g'-average from 0.9 to 1.0. Embodiment 18. The method of embodiment 16 or 17, wherein the copolymer further comprises a first peak elution temperature less than 30°C and a second peak elution temperature greater than 40°C. Embodiment 19. The method of any one of embodiments 16-18, wherein the copolymer further comprises an r1r2 reactivity ratio of 0.2 to 0.8.

[0065] Embodiment 20. The method of any of embodiments 16-19, wherein the copolymer further comprises less than 10% by weight of diene-derived units, and the at least one C3-C20 comonomer is butene or octene, or a combination thereof. Certain embodiments and features are described using a set of upper numerical limits and a set of lower numerical limits. It should be understood that ranges including any combination of two values ​​are contemplated, for example, any combination of a lower limit with any upper limit, any combination of two lower limits, and / or any combination of two upper limits, unless otherwise specified. Certain lower limits, upper limits, and ranges are set forth in one or more claims below. All numerical values ​​are "about" or "approximately" stated and account for experimental error and variation that would be expected by one of ordinary skill in the art.

[0066] Various terms are defined above. To the extent a term used in the claims is not defined above, it should be given the broadest definition that one of ordinary skill in the art would give that term as reflected in at least one printed publication or issued patent. Furthermore, all patents, test procedures, and other documents cited in this application are incorporated by reference in their entirety to the extent such disclosure is not inconsistent with this application and in all jurisdictions where such incorporation is permitted.

[0067] While the forgoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, which scope is determined by the claims that follow.

Claims

1. at least 50% by weight of ethylene-derived units, and at least 20% by weight of at least one C3-C20 comonomer An ethylene copolymer comprising: a melt index of 0.5 g / 10 min to about 50 g / 10 min, measured according to ASTM D1238 (190° C. / 2.16 kg); a density of about 0.860 g / cc to 0.880 g / cc, measured in accordance with ASTM D792; a first long chain branching index (g'(Mz)) of 0.80 to 0.93; a second long chain branching index (g'(Mz+1)) of 0.80 to 0.93; vinyl / total unsaturation less than 0.7; an unsaturation level of a trisubstituted olefin of 50 to 500; and 4 x 10 15 Volume resistivity at 23°C of Ωcm or more An ethylene copolymer having the formula:

2. 10. The ethylene copolymer of claim 1 further having a ratio of g'Mz+1 / g'-average from 0.9 to 1.

0.

3. 10. The ethylene copolymer of claim 1 having a vinyl / total unsaturation of less than 0.

6.

4. 2. The ethylene copolymer of claim 1, wherein the trisubstituted olefin has an unsaturation level of 60 to 450.

5. 10. The ethylene copolymer of claim 1, further having two or more TREF elution temperature peaks.

6. 10. The ethylene copolymer of claim 1, further having a first peak elution temperature less than 30°C and a second peak elution temperature greater than 40°C.

7. 10. The ethylene copolymer of claim 1, further having an r1r2 reactivity ratio of 0.8 or less.

8. 10. The ethylene copolymer of claim 1 further having an r1r2 reactivity ratio of 0.2 to 0.

8.

9. 10. The ethylene copolymer of claim 1, further comprising less than 10% by weight of diene-derived units.

10. 2. The ethylene copolymer of claim 1, wherein the at least one C3-C20 comonomer is butene or octene or a combination thereof.

11. at least one electronic device; and ETHYLENE COPOLYMER FILM IN DIRECT CONTACT WITH AT LEAST ONE SURFACE OF AN ELECTRONIC DEVICE - Patent application 1. An electronic device module comprising: at least 50% by weight of ethylene-derived units, and at least 20% by weight of at least one C3-C20 comonomer and the copolymer comprises a melt index of 0.5 g / 10 min to about 50 g / 10 min, measured according to ASTM D1238 (190° C. / 2.16 kg); a density of about 0.860 g / cc to 0.880 g / cc, measured in accordance with ASTM D792; a first long chain branching index (g'(Mz)) of 0.80 to 0.93; a second long chain branching index (g'(Mz+1)) of 0.80 to 0.93; vinyl / total unsaturation less than 0.7; an unsaturation level of a trisubstituted olefin of 50 to 500; and 4 x 10 15 Volume resistivity at 23°C of Ωcm or more An electronic device module having:

12. 12. The electronic device module of claim 11, wherein the copolymer further has a ratio of g'Mz+1 / g'-average from 0.9 to 1.

0.

13. 13. The electronic device module of claim 12, wherein the copolymer further has a first peak elution temperature less than 30°C and a second peak elution temperature greater than 40°C.

14. The electronic device module of claim 13, wherein the copolymer further has an r1r2 reactivity ratio of 0.2 to 0.

8.

15. 15. The electronic device module of claim 14, wherein the copolymer further comprises less than 10% by weight of diene-derived units, and the at least one C3-C20 comonomer is butene or octene or a combination thereof.

16. 1. A method for manufacturing an electronic device module, comprising: Providing at least one electronic device; and laminating an ethylene copolymer film to at least one surface of the electronic device; and the ethylene copolymer comprises at least 50% by weight of ethylene-derived units, and at least 20% by weight of at least one C3-C20 comonomer and the copolymer comprises a melt index of 0.5 g / 10 min to about 50 g / 10 min, measured according to ASTM D1238 (190° C. / 2.16 kg); a density of about 0.860 g / cc to 0.880 g / cc, measured in accordance with ASTM D792; a first long chain branching index (g'(Mz)) of 0.80 to 0.93; a second long chain branching index (g'(Mz+1)) of 0.80 to 0.93; vinyl / total unsaturation less than 0.7; an unsaturation level of a trisubstituted olefin of 50 to 500; and 4 x 10 15 Volume resistivity at 23°C of Ωcm or more A method comprising:

17. 17. The method of claim 16, wherein the copolymer further has a ratio of g'Mz+1 / g'-average from 0.9 to 1.

0.

18. 18. The method of claim 17, wherein the copolymer further has a first peak elution temperature less than 30°C and a second peak elution temperature greater than 40°C.

19. 20. The method of claim 18, wherein the copolymer further has an r1r2 reactivity ratio of 0.2 to 0.

8.

20. 20. The method of claim 19, wherein the copolymer further comprises less than 10% by weight of diene-derived units, and the at least one C3-C20 comonomer is butene or octene or a combination thereof.

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