Polyethylene compositions, films and articles

Abstract

Embodiments of a polyethylene composition are provided that can include: a first polyethylene fraction having at least one peak in a temperature range from 40°C to 75°C in an elution profile obtained by a modified comonomer composition distribution (iCCD) analysis method, wherein a first polyethylene area fraction is an area from 40°C to 75°C in the elution profile, and wherein the first polyethylene fraction area comprises from 45% to 65% of a total area of the elution profile; and a second polyethylene fraction having at least one peak in a temperature range from 85°C to 110°C in the elution profile, wherein a second polyethylene area fraction is an area from 85°C to 110°C in the elution profile, and wherein the second polyethylene fraction area comprises from 15% to 35% of the total area of the elution profile, wherein the polyethylene composition has a density from 0.905 g / cm3to 0.918 g / cm3, a melt index (I2) from 0.7 g / 10 min to 3.5 g / 10 min, and wherein a melt index ratio (I 10 / I2) of the composition satisfies the following equation: I 10 / I2<7.0 - 1.2 log(I2).

Description

Technical Field

[0001] This application relates to polymer compositions, films comprising such polyethylene compositions, and articles thereof. Background Technology

[0002] The use of polyolefin compositions in packaging applications is well-known. Such polyolefin compositions can be produced using a variety of conventional methods. Various polymerization techniques using different catalyst systems have been used to produce these polyolefin compositions suitable for packaging applications. However, despite efforts to develop compositions suitable for packaging applications in some embodiments, there remains a need for improved polyethylene compositions suitable for packaging applications that offer a good balance of properties and processability at the desired polymer composition density. Summary of the Invention

[0003] This application discloses polyethylene compositions suitable for packaging applications, films, multilayer structures, and articles made therefrom. In some embodiments, the polyethylene compositions disclosed herein are suitable as sealant layers for films to be used in packaging applications.

[0004] Conventional films (such as those utilizing a sealant layer) typically involve a trade-off between the hot tack initiation temperature, the heat seal initiation temperature, or both, and the total density of the film. The density of the composition affects the processing characteristics of the film. For example, films containing conventional polyethylene compositions with relatively low densities tend to exhibit lower hot tack initiation temperatures, heat seal initiation temperatures, or both, compared to films containing compositions with relatively high total densities. Polyethylene compositions with relatively low densities can also be particularly difficult to process in conventional blown film applications due to the material's very low melting point and tacky or sticky nature. Conversely, films with relatively high total densities typically exhibit higher hot tack initiation temperatures, heat seal initiation temperatures, or both. In some packaging applications, lower hot tack and heat seal initiation temperatures can be desirable polymer performance characteristics. Therefore, there remains a need for polyethylene compositions that provide improved hot tack window, hot tack strength, and / or heat seal initiation temperature when used in the sealant layer of a film. In various embodiments, the polyethylene compositions disclosed herein can be used in films to provide improved hot tack window, hot tack strength, and / or heat seal initiation temperature when used in the sealant layer.

[0005] As described in detail herein, polymer compositions can be evaluated using improved comonomer composition distribution (iCCD) analysis. Embodiments of this disclosure can meet the aforementioned requirements regarding a wide hot tack window, hot tack strength, and / or heat-sealing onset temperature by providing the following polyethylene compositions, in some embodiments of which, according to iCCD analysis, the polyethylene composition contains at least two polyethylene fractions within a specific temperature range, each fraction comprising a desired percentage of the total area of ​​the elution curve. Such polyethylene compositions can have the desired hot tack window, hot tack strength, and / or heat-sealing onset temperature, or both, while possessing, for example, at least 0.905 g / cm³. 3 The density. Unbound by theory, it is believed that at least some currently described polyethylene compositions may possess such properties, at least in part due to specific multi-peak elution profiles, in which the first and second polyethylene fractions exhibit peaks at temperatures of 40°C to 75°C and 85°C to 110°C, respectively, in the elution profiles analyzed by iCCD.

[0006] According to one or more embodiments, a polyethylene composition suitable for packaging applications comprises (a) a first polyethylene fraction having a single peak in an elution profile obtained by an improved comonomer composition distribution (iCCD) analysis method in a temperature range of 40°C to 75°C, wherein the first polyethylene area fraction is the area below the single peak of the first polyethylene fraction in the elution profile between 40°C and 75°C, and wherein the area of ​​the first polyethylene fraction accounts for 45% to 65% of the total area of ​​the elution profile; and (b) in an iCCD analysis... The second polyethylene fraction in the elution curve obtained by the analytical method is located in the temperature range of 85°C to 110°C, and the area fraction of the second polyethylene fraction is the area below the single peak of the second polyethylene fraction in the elution curve between 85°C and 110°C, and the area fraction of the second polyethylene fraction is the area below at least one peak of the second polyethylene fraction in the elution curve between 85°C and 110°C, and the area of ​​the second polyethylene fraction accounts for 15% to 35% of the total area of ​​the elution curve; the density of the polyethylene composition is 0.905 g / cm³. 3 Up to 0.918 g / cm 3 The melt index (I2) is 0.7 g / 10 min to 3.5 g / 10 min, and the melt index ratio of the composition is (I2) 10 / I2) satisfies the following equation: I 10 / I2<7.0–1.2log(I2).

[0007] According to one or more embodiments, the membrane may contain the polyethylene composition described above or in any other embodiments described herein.

[0008] According to one or more embodiments, the article may contain the polyethylene composition described above or in any other embodiments described herein. Attached Figure Description

[0009] The following detailed description of specific embodiments of this disclosure is best understood in conjunction with the following drawings, in which similar reference numerals indicate similar structures and in the drawings:

[0010] Figure 1 The iCCD elution curves according to one or more embodiments described herein are schematically depicted; and

[0011] Figure 2 A reactor system for producing polyethylene is schematically depicted according to one or more embodiments described herein; Detailed Implementation

[0012] This document describes embodiments of a polyethylene composition. Such a polyethylene composition can be used, for example, in packaging applications. The polyethylene composition may comprise a first polyethylene fraction and a second polyethylene fraction. The polyethylene composition may be contained in films (including single-layer and multi-layer films) or other articles (such as multilayer structures and packaging).

[0013] As described herein, “polyethylene” or “ethylene-based polymer” refers to a polymer comprising a majority amount (>50 mol%) of units derived from ethylene monomers. This includes polyethylene homopolymers or copolymers (meaning units derived from two or more comonomers). Common forms of polyethylene known in the art include low-density polyethylene (LDPE); linear low-density polyethylene (LLDPE); ultra-low-density polyethylene (ULDPE); very low-density polyethylene (VLDPE); single-point catalytic linear low-density polyethylene, including linear and substantially linear low-density resins (m-LLDPE); ethylene-based plastomers and ethylene-based elastomers; medium-density polyethylene (MDPE); and high-density polyethylene (HDPE). These polyethylene materials are generally known in the art; however, the following description may help to understand the differences between some of these different polyethylene resins.

[0014] As used herein, the term "composition" refers to a mixture of materials comprising the composition, as well as reaction products and decomposition products formed from the materials of the composition.

[0015] The term "LDPE" can also be referred to as "high-pressure ethylene polymer" or "highly branched polyethylene," and it can be defined as meaning that the polymer is partially or completely homopolymerized or copolymerized in an autoclave or tubular reactor at pressures above 14,500 psi (100 MPa) using a free radical initiator (such as peroxide) (see, for example, US 4,599,392, which is hereby incorporated herein by reference). The density of LDPE resin is typically around 0.916 g / cm³. 3 Up to 0.935 g / cm 3 Within the range.

[0016] The term "LLDPE" encompasses two resins prepared using conventional Ziegler-Natta catalyst systems and chromium-based catalyst systems, as well as single-site catalysts (including, but not limited to, substituted mono- or dicyclopentadienyl catalysts (commonly referred to as metallocenes), confined geometry catalysts, phosphine imine catalysts, and polyvalent aryloxy ether catalysts (commonly referred to as diphenylphenoxys), and comprising linear, substantially linear, or heterogeneous polyethylene copolymers or homopolymers. Compared to LDPE, LLDPE comprises less long-chain branching and comprises substantially linear ethylene polymers, as further defined in U.S. Patents 5,272,236, 5,278,272, 5,582,923, and 5,733,155; homogeneous branched linear ethylene polymer compositions, such as those in U.S. Patent No. 3,645,992; multiphase branched ethylene polymers, such as those prepared according to the process disclosed in U.S. Patent No. 4,076,698; and / or blends thereof (such as those in U.S. Patent No. 4,076,698). (Those disclosed in US 3,914,342 or US 5,854,045). LLDPE can be prepared by gas-phase, solution-phase, or slurry polymerization or any combination thereof, using any type of reactor or reactor configuration known in the art.

[0017] The term "MDPE" refers to a material with a density of 0.924 g / cm³. 3 Up to 0.936 g / cm 3 Polyethylene. “MDPE” is typically prepared using chromium or Ziegler-Natta catalysts or using single-point catalysts, including but not limited to substituted mono- or di-cyclopentadienyl catalysts (commonly known as metallocenes), confined geometry catalysts, phosphine imine catalysts, and polyvalent aryloxy ether catalysts (commonly known as diphenylphenoxy).

[0018] The term "HDPE" refers to a material with a density greater than approximately 0.935 g / cm³. 3 And at most about 0.980 g / cm 3Polyethylene is generally prepared using Ziegler-Natta catalysts, chromium catalysts, or single-point catalysts (including but not limited to substituted mono- or di-cyclopentadienyl catalysts (commonly known as metallocenes), confined geometry catalysts, phosphine imine catalysts, and polyvalent aryloxy ether catalysts (commonly known as bisphenylphenoxy).

[0019] The term "ULDPE" refers to a material with a density of 0.855 g / cm³. 3 Up to 0.912 g / cm 3 Polyethylene, typically prepared using Ziegler-Natta catalysts, chromium catalysts, or single-point catalysts (including but not limited to substituted mono- or di-cyclopentadienyl catalysts (commonly known as metallocenes), confined geometry catalysts, phosphine-imine catalysts, and polyvalent catalysts (commonly known as bisphenylphenoxys)). ULDPE includes, but is not limited to, polyethylene (ethylene-based) plastomers and polyethylene (ethylene-based) elastomers. Polyethylene (ethylene-based) elastomers or plastomers typically have a strength of 0.855 to 0.912 g / cm³. 3 The density.

[0020] The terms “blend,” “polymer blend,” and similar terms mean a composition of two or more polymers. Such a blend may or may not be miscible. Such a blend may or may not be phase-separated. As determined by transmission electron spectroscopy, light scattering, X-ray scattering, and any other method known in the art, such a blend may or may not contain one or more domain configurations. The blend is not a laminate, but one or more layers of a laminate may contain the blend. This blend can be prepared as a dry blend, in-situ formed (e.g., in a reactor), melt blend, or using other techniques known to those skilled in the art.

[0021] Unless stated to the contrary, implied by the context or customary in the art, all parts and percentage values ​​are by weight, all temperatures are in °C, and all test methods are current methods as of the date of this disclosure.

[0022] The terms “comprising,” “including,” “having,” and their derivatives are not intended to exclude the presence of any additional components, steps, or procedures, whether or not such components, steps, or procedures are specifically disclosed. For the avoidance of any doubt, unless stated to the contrary, all compositions claimed using the term “comprising” may include any additional additives, adjuvants, or compounds, whether polymerized or otherwise. The term “composes of” excludes any ingredients, steps, or procedures not specifically described or listed.

[0023] Polyethylene Composition and Characterization

[0024] In one or more embodiments, the density of the polyethylene composition may be 0.905 g / cm³. 3 Up to 0.918 g / cm 3 For example, the density of the polyethylene composition embodiments disclosed herein may be: 0.905 g / cm³. 3 Up to 0.916 g / cm 3 0.905g / cm 3 Up to 0.915 g / cm 3 0.905g / cm 3 Up to 0.914 g / cm 3 0.905g / cm 3 Up to 0.912 g / cm 3 0.907 g / cm 3 Up to 0.918 g / cm 3 0.907 g / cm 3 Up to 0.916 g / cm 3 0.907 g / cm 3 Up to 0.914 g / cm 3 0.907 g / cm 3 Up to 0.912 g / cm 3 0.909 g / cm 3 Up to 0.918 g / cm 3 0.909 g / cm 3 Up to 0.916 g / cm 3 0.909 g / cm 3 Up to 0.914 g / cm 3 0.910 g / cm 3 Up to 0.918 g / cm 3 0.910 g / cm 3 Up to 0.916 g / cm 3 0.910 g / cm 3 Up to 0.914 g / cm 3 Or any combination of these ranges.

[0025] In one or more embodiments, the melt index (I2) of the polyethylene composition may be from 0.70 g / 10 min to 3.5 g / 10 min. For example, in one or more embodiments, the melt index (I2) of the polyethylene composition may be from 0.7 g / 10 min to 3.0 g / 10 min, 0.7 g / 10 min to 2.5 g / 10 min, 0.7 g / 10 min to 2.0 g / 10 min, 0.7 g / 10 min to 1.5 g / 10 min, 0.85 g / 10 min to 3.5 g / 10 min, 0.85 g / 10 min to 3.0 g / 10 min, 0.85 g / 10 min to 2.5 g / 10 min, 0.85 g / 10 min to 2.0 g / 10 min, 0.85 g / 10 min to 1.5 g / 10 min, or any combination of these ranges.

[0026] In one or more embodiments, the melt index ratio (I) of the polyethylene composition is... 10 The melt index ratio (I2) can be less than 7.0. For example, in one or more embodiments, the melt index ratio (I2) of the polyethylene composition is... 10 / I2) can be 6.0 to 6.9, 6.0 to 6.7, 6.0 to 6.4, or any combination of these ranges.

[0027] In one or more embodiments, the polyethylene composition may have a melt index ratio (I) that satisfies the following equation. 10 / I2):I 10 / I2<7.0–1.2log(I2).

[0028] In one or more embodiments, the molecularly weighted comonomer distribution index (MWCDI) of the polyethylene composition may be less than 1.0. For example, in one or more embodiments, the MWCDI of the polyethylene composition may be 0.0 to 2.0, 0.0 to 1.5, 0.0 to 1.0, 0.0 to 0.5, 0.1 to 1.0, 0.1 to 1.5, or any combination of these ranges.

[0029] According to one or more embodiments, the weight-average molecular weight (M) of the polyethylene composition w The weight-average molecular weight (M) of the polyethylene composition can range from 100,000 g / mol to 130,000 g / mol. For example, in one or more embodiments, the weight-average molecular weight (M) of the polyethylene composition... wIt may be 105,000 g / mol to 130,000 g / mol, 105,000 g / mol to 125,000 g / mol, 105,000 g / mol to 120,000 g / mol, 105,000 g / mol to 115,000 g / mol, 110,000 g / mol to 130,000 g / mol, 110,000 g / mol to 125,000 g / mol, 110,000 g / mol to 120,000 g / mol, 115,000 g / mol to 130,000 g / mol, or any combination of these ranges.

[0030] According to one or more embodiments, the molecular weight distribution of the polyethylene composition, expressed as a weight-average molecular weight to number-average molecular weight ratio (Mw / Mn), can be in the range of 2.0 to 4.0. For example, the molecular weight distribution of the polyethylene composition can be 2.0 to 3.5, 2.5 to 4.0, 2.5 to 3.5, 2.0 to 3.3, 2.0 to 3.2, 2.5 to 3.3, 2.5 to 3.2, or any combination of these ranges. As described herein, the molecular weight distribution can be calculated using gel permeation chromatography (GPC) techniques as described herein.

[0031] According to one or more embodiments, the z-average molecular weight (M) of the polyethylene composition z The z-average molecular weight (M) of a polyethylene composition can be less than 300,000 g / mol. z It may be 230,000 g / mol to 300,000 g / mol, 240,000 g / mol to 300,000 g / mol, 250,000 g / mol to 300,000 g / mol, 260,000 g / mol to 300,000 g / mol, 270,000 g / mol to 300,000 g / mol, 230,000 g / mol to 290,000 g / mol, 240,000 g / mol to 290,000 g / mol, 250,000 g / mol to 290,000 g / mol, 260,000 g / mol to 290,000 g / mol, 270,000 g / mol to 290,000 g / mol, or any combination of these ranges.

[0032] According to one or more other embodiments, the polyethylene component may have a zero-shear viscosity ratio of less than 2.0. For example, the zero-shear viscosity ratio of the polyethylene composition may be less than 1.9, less than 1.8, less than 1.7, less than 1.6, less than 1.5, less than 1.4, less than 1.3, less than 1.2, or even less than 1.1. In one or more embodiments, the polyethylene component may have a zero-shear viscosity ratio of at least 1.0. In embodiments, the zero-shear viscosity ratio of the polyethylene composition may be in the range of: 1.0 to 2.0, 1.0 to 1.8, 1.0 to 1.6, 1.0 to 1.4, 1.0 to 1.2, 1.2 to 2.0, 1.2 to 1.8, 1.2 to 1.6, 1.2 to 1.4, 1.4 to 2.0, 1.4 to 1.8, 1.4 to 1.6, 1.6 to 2.0, 1.6 to 1.8, or 1.8 to 2.0, or any combination of these ranges.

[0033] tanδ refers to how closely a material approximates a perfectly elastic solid (where d = 0°, tanδ = 0) or a perfectly Newtonian liquid (where d = 90°, tanδ ≈ infinity). Therefore, the lower the value of tanδ, the greater the elasticity of the material. tanδ is a function of long-chain branching (LCB) and molecular weight distribution (MWD) at the same total molecular weight. A larger value of tanδ indicates a lower LCB. In embodiments, the polyethylene composition may have tanδ in the following ranges at 0.1 radians / second and 190°C: 6 to 100, 6 to 90, 6 to 80, 6 to 70, 6 to 60, 6 to 50, 6 to 40, 6 to 30, 6 to 20, 20 to 100, 20 to 90, 20 to 80, 20 to 70, 20 to 60, 20 to 50, 20 to 40, 20 to 30, 30 to 100, 30 to 90, 30 to 80, 30 to 70. 30 to 60, 30 to 50, 30 to 40, 40 to 100, 40 to 90, 40 to 80, 40 to 70, 40 to 60, 40 to 50, 50 to 100, 50 to 90, 50 to 80, 50 to 70, 50 to 60, 60 to 100, 60 to 90, 60 to 80, 60 to 70, 70 to 100, 70 to 90, 70 to 80, 80 to 100, 80 to 90, or 90 to 100, or any combination of these ranges.

[0034] As described herein, a polyethylene “fraction” refers to a portion of the total composition of a polyethylene component. Currently disclosed embodiments may include at least a “first polyethylene fraction” and a “second polyethylene fraction,” and embodiments may also include a “third polyethylene fraction.” Various fractions included in a polyethylene composition can be defined by their temperature range in an elution profile using an improved comonomer composition distribution (iCCD) analysis method. For example, a polyethylene fraction may be defined by a range from lower to higher temperatures. It should be understood that two or more polyethylene fractions may overlap. In one or more embodiments, a polyethylene fraction may be substantially correlated with a peak or trough in the iCCD data. In one or more embodiments, a particular polyethylene fraction may include a specified percentage of the total area of ​​the polyethylene composition defined by an iCCD analysis elution profile. Unless otherwise stated, any elution profiles mentioned herein are elution profiles observed by iCCD. Examples of such fractions will be better understood given the embodiments provided herein.

[0035] Typically, the first fraction may include at least one peak within the temperature range of the first fraction. The second fraction may include at least one peak within the temperature range of the second fraction. The polyethylene compositions described herein may be referred to as "multimodal," meaning that they include at least two peaks in their elution profile. In embodiments, the polyethylene compositions described herein may include ("bimodal"), three peaks ("trimodal"), or more than three peaks in their elution profile. The first polyethylene area fraction, the second polyethylene fraction, and the third polyethylene fraction may each comprise a portion of the total mass of the polyethylene composition.

[0036] Referring to the described iCCD distribution, Figure 1 The iCCD distribution of the sample is schematically depicted. Figure 1 This section generally depicts several characteristics of the iCCD curves of the polyethylene compositions currently described in detail herein, such as the first polyethylene fraction, the second fraction, the third polyethylene fraction, etc. Therefore, Figure 1 This can be used as a reference for publicly available information related to the iCCD curves provided in this article.

[0037] Specifically, the first polyethylene fraction 102, the second polyethylene fraction 104, and the third polyethylene fraction 106 are described. The first polyethylene fraction 102 has a peak 112, and the second polyethylene fraction 104 has a peak 114. It should be understood that... Figure 1 The curves are not derived from experiments or observations, but rather provide information for the purpose of describing specific characteristics of iCCD elution curves.

[0038] In one or more embodiments, one or more of the first polyethylene fraction and the second polyethylene fraction may have a single peak. As used herein, "single peak" means an iCCD in which a particular fraction includes only a single peak. That is, in some embodiments, the iCCD of one or more of the first polyethylene fraction and the second polyethylene fraction includes only an upwardly sloping region followed by a downwardly sloping region to form a single peak.

[0039] It should be understood that peaks in one or more of the first and second polyethylene fractions may not be formed by local minima of the corresponding polyethylene fraction at defined temperature boundaries. That is, the peaks must be peaks across the entire spectral range, not peaks formed by the threshold temperature of the polyethylene fraction. For example, if a polyethylene fraction contains a single peak followed by a single valley (sloping upwards, then downwards, then upwards again), then only a single peak will exist in such a polyethylene fraction.

[0040] In one or more embodiments, the first polyethylene fraction 102 may be the area of ​​the elution curve at 40°C to 75°C. In another embodiment, the first polyethylene fraction 102 may be the area of ​​the elution curve obtained by iCCD within the temperature range of 40°C to 60°C, 40°C to 50°C, 40°C to 70°C, 40°C to 65°C, 50°C to 75°C, 50°C to 70°C, 50°C to 65°C, 60°C to 75°C, 60°C to 70°C, or any combination thereof.

[0041] According to one or more embodiments, the area of ​​the first polyethylene fraction may account for 45% to 65% of the total area of ​​the elution curve. For example, the area of ​​the first polyethylene fraction may account for 45% to 60%, 45% to 55%, 45% to 50%, 50% to 65%, 50% to 60%, 50% to 55%, 55% to 65%, or any combination thereof.

[0042] In one or more embodiments, the first polyethylene fraction 102 may have at least one peak 112 in the elution profile obtained by the iCCD within a temperature range of 40°C to 75°C. In one or more embodiments, the first polyethylene fraction 102 may have at least one peak 112 in the elution profile obtained by the iCCD within a temperature range of 40°C to 60°C, 40°C to 50°C, 40°C to 70°C, 40°C to 65°C, 50°C to 75°C, 50°C to 70°C, 50°C to 65°C, 60°C to 75°C, 60°C to 70°C, or any combination thereof.

[0043] In one or more embodiments, the weight-average molecular weight (M) of the first polyethylene fraction wThe molecular weight can be less than or equal to 150,000 g / mol, such as 100,000 g / mol to 150,000 g / mol, 110,000 g / mol to 150,000 g / mol, 120,000 g / mol to 150,000 g / mol, 100,000 g / mol to 140,000 g / mol, 110,000 g / mol to 140,000 g / mol, 120,000 g / mol to 140,000 g / mol, or any combination of these ranges. The molecular weight of the polyethylene fraction can be calculated based on iCCD results, as described below.

[0044] The temperature range (40°C to 75°C) of the first polyethylene fraction may be ideal because it corresponds to the low-density component of the polyethylene composition. In embodiments, the low-density component can provide a low heat-tack initiation temperature, heat-seal initiation temperature, or both. Therefore, adding a first polyethylene fraction 102 that may include a low-density component can thus enable the formation of an airtight seal in a package containing a sealant layer of such resin at a lower sealing temperature.

[0045] In one or more embodiments, the second polyethylene fraction 104 may be the area in the elution curve at 85°C to 110°C. In another embodiment, the second polyethylene fraction 104 may be the area in the elution curve obtained by iCCD within the temperature range of 85°C to 105°C, 85°C to 100°C, 85°C to 90°C, 90°C to 110°C, 90°C to 105°C, 90°C to 100°C, 95°C to 110°C, 95°C to 105°C, 100°C to 110°C, or any combination thereof.

[0046] According to one or more embodiments, the area of ​​the second polyethylene fraction may account for 15% to 35% of the total area of ​​the elution curve. For example, the area of ​​the second polyethylene fraction may account for 20% to 35%, 25% to 35%, 15% to 30%, 20% to 30%, 20% to 25%, 15% to 25%, 15% to 20%, 20% to 30%, 20% to 25%, 25% to 30%, or any combination thereof.

[0047] In one or more embodiments, the second polyethylene fraction 104 may have at least one peak 114 in the elution profile obtained by iCCD within a temperature range of 85°C to 110°C. In one or more embodiments, the second polyethylene fraction 104 may have at least one peak 114 in the elution profile obtained by iCCD within a temperature range of 85°C to 105°C, 85°C to 100°C, 85°C to 90°C, 90°C to 110°C, 90°C to 105°C, 90°C to 100°C, 95°C to 110°C, 95°C to 105°C, 100°C to 110°C, or any combination thereof.

[0048] In one or more embodiments, the weight-average molecular weight (M) of the second polyethylene fraction w The concentration can be less than or equal to 190,000 g / mol, such as 95,000 g / mol to 190,000 g / mol, 100,000 g / mol to 190,000 g / mol, 105,000 g / mol to 190,000 g / mol, 110,000 g / mol to 190,000 g / mol, 95,000 g / mol to 180,000 g / mol, 100,000 g / mol to 180,000 g / mol. The molecular weight of the polyethylene fraction can be calculated based on iCCD results, as described below. The molecular weights range from 105,000 g / mol to 180,000 g / mol, 110,000 g / mol to 180,000 g / mol, 95,000 g / mol to 150,000 g / mol, 100,000 g / mol to 150,000 g / mol, 105,000 g / mol to 150,000 g / mol, 110,000 g / mol to 150,000 g / mol, or any combination of these ranges.

[0049] The temperature range (85°C to 110°C) of the second polyethylene fraction is likely ideal because it corresponds to the high-density component. In an embodiment, increasing the high-density component can increase the total density of the polyethylene composition. Therefore, increasing the second polyethylene fraction 104 can thereby increase the high-density component and provide a polyethylene composition with a higher total density. Furthermore, increasing the second polyethylene fraction 104 can improve the adhesiveness of the polyethylene composition. Without being bound by theory, it is believed that larger crystals form in the high-density fraction, which provides a rough surface. A rough surface can reduce the contact area and thus improve the adhesiveness of the polyethylene composition.

[0050] In one or more embodiments, the polyethylene composition may have a local minimum in the temperature range of 75°C to 85°C in the elution profile obtained by iCCD. This local minimum may fall between peak 112 of the first polyethylene fraction 102 and peak 114 of the second polyethylene fraction 104.

[0051] In one or more embodiments, the third polyethylene area fraction 106 may be the area at 75°C to 85°C in the elution curve obtained by iCCD.

[0052] According to one or more embodiments, the area of ​​the third polyethylene fraction may be less than 25% of the total area of ​​the elution curve (e.g., less than 23%, less than 22%, or less than 20% of the total area of ​​the elution curve). For example, the area of ​​the third polyethylene fraction may be 5% to 25%, 8% to 25%, 10% to 25%, 12% to 25%, 15% to 25%, 5% to 23%, 8% to 23%, 10% to 23%, 12% to 23%, 15% to 23%, or any combination thereof.

[0053] In one or more embodiments, the weight-average molecular weight (M) of the third polyethylene fraction w The concentration can be less than or equal to 140,000 g / mol, such as 80,000 g / mol to 140,000 g / mol, 85,000 g / mol to 140,000 g / mol, 90,000 g / mol to 140,000 g / mol, 95,000 g / mol to 140,000 g / mol, 100,000 g / mol to 140,000 g / mol, 85,000 g / mol to 130,000 g / mol, 90,000 g / mol to 140,000 g / mol, 90,000 g / mol to 140,000 g / mol, 95,000 g / mol to 140,000 g / mol, 90,000 g / mol to 140,000 g / mol, 90,000 g / mol to 140,000 g / mol, 95,000 g / mol to 130,000 g / mol, 90,000 g / mol to 140,000 g / mol, 90,000 g / mol to 140,000 g / mol, 95 ...5, The molecular weight of the polyethylene fraction can be calculated based on iCCD results, as described below. The molecular weight ranges are 95,000 g / mol to 130,000 g / mol, 100,000 g / mol to 130,000 g / mol, 85,000 g / mol to 125,000 g / mol, 90,000 g / mol to 125,000 g / mol, 95,000 g / mol to 125,000 g / mol, 100,000 g / mol to 125,000 g / mol, or any combination of these ranges.

[0054] In various embodiments, the weight-average molecular weight (M) of the polyethylene composition in various polyethylene fractions w The ratio of M to ) may be important. In one or more embodiments, M in the first polyethylene fraction (40°C to 75°C) w M in the third polyethylene grade (75°C to 85°C) w The ratio (i.e., M of the first polyethylene fraction) w Divided by M of the third polyethylene fraction w The value is 0.90 to 1.6. For example, M in the first polyethylene grade (40°C to 75°C) w M in the third polyethylene grade (75°C to 85°C) w The ratio (i.e., M of the first polyethylene fraction) w Divided by M of the third polyethylene fraction wThe value can be 1.0 to 1.6, 1.1 to 1.6, 1.2 to 1.6, 0.90 to 1.5, 1.0 to 1.5, 1.1 to 1.5, 1.2 to 1.5, 0.90 to 1.4, 1.0 to 1.4, 1.1 to 1.4, or any combination of these ranges.

[0055] In one or more embodiments, M in the third polyethylene fraction (75°C to 85°C) w M in the second polyethylene fraction (85°C to 110°C) w The ratio (i.e., the M of the third polyethylene fraction) w Divided by M of the second polyethylene fraction w The value is 0.50 to 1.5. For example, M in the third polyethylene fraction (75°C to 85°C) w M in the second polyethylene fraction (85°C to 110°C) w The ratio (i.e., the M of the third polyethylene fraction) w Divided by M of the second polyethylene fraction w The value can be 0.50 to 1.4, 0.50 to 1.3, 0.50 to 1.2, 0.50 to 1.1, 0.50 to 1.0, 0.50 to 0.90, 0.60 to 1.4, 0.60 to 1.3, 0.60 to 1.2, 0.60 to 1.1, 0.60 to 1.0, 0.60 to 0.90, 0.70 to 1.4, 0.70 to 1.3, 0.70 to 1.2, 0.70 to 1.1, 0.70 to 1.0, 0.70 to 0.90, or any combination of these ranges.

[0056] In one or more embodiments, the polyethylene composition is formed by the polymerization of ethylene and a comonomer (such as a C3–C12 olefin). Considered comonomers include C6–C9 olefins, such as 1-octene and 1-hexene. In one or more embodiments, the comonomer is 1-octene.

[0057] In one or more embodiments, the polyethylene compositions disclosed herein may also comprise additional components, such as one or more additives. Such additives include, but are not limited to, antistatic agents, colorants, dyes, lubricants, fillers (such as TiO2 or CaCO3), opacifiers, nucleating agents, processing aids, pigments, primary antioxidants, secondary antioxidants, UV stabilizers, anti-caking agents, slip agents, lubricants, flame retardants, antimicrobial agents, deodorizers, antifungal agents, and combinations thereof. Based on the weight of the polyethylene composition containing such additives, the polyethylene composition may comprise from about 0.1% to about 10% of the total weight of such additives.

[0058] polymerization

[0059] The polyethylene components described herein can be produced using any conventional polymerization method. Such conventional polymerization methods include, but are not limited to, gas-phase polymerization, slurry polymerization, and solution polymerization methods using one or more conventional reactors, such as loop reactors, isothermal reactors, stirred tank reactors, tubular reactors, plug flow reactors, batch reactors, and / or any combination thereof. The polyethylene compositions can be produced, for example, via solution-phase polymerization using one or more loop reactors, isothermal reactors, and combinations thereof.

[0060] Typically, solution-phase polymerization can be carried out at temperatures ranging from 115°C to 250°C (e.g., 115°C to 210°C) and pressures ranging from 300 psi to 3,000 psi (e.g., 400 psi to 800 psi) in one or more well-mixed reactors, such as one or more isothermal loop reactors or one or more adiabatic reactors. In one embodiment, in a dual-reactor configuration, the temperature in the first reactor is in the range of 115°C to 190°C (e.g., 150°C to 180°C), while the temperature in the second reactor is in the range of 150°C to 250°C (e.g., 180°C to 220°C). In another embodiment, in a single reactor, the temperature in the reactor is in the range of 115°C to 250°C (e.g., 115°C to 225°C).

[0061] Residence times in solution-phase polymerization are typically in the range of 2 to 30 minutes (e.g., 5 to 25 minutes). Ethylene, solvent, hydrogen, one or more catalyst systems, optionally one or more cocatalysts, and optionally one or more comonomers are continuously fed into one or more reactors. Exemplary solvents include, but are not limited to, isoparaffins. For example, such solvents may be available under the name ISOPAR E from ExxonMobil Chemical Co., Houston, Texas. The resulting mixture of the polyethylene composition and solvent is then removed from the reactor, and the polyethylene composition is separated. The solvent is typically recovered via a solvent recovery unit (i.e., a heat exchanger and a vapor-liquid separator drum) and subsequently recycled back into the polymerization system.

[0062] In some embodiments, the polyethylene component can be produced via solution polymerization in a two-reactor system (e.g., a dual loop reactor system), wherein ethylene is polymerized in the presence of one or more catalyst systems and one or more comonomers. Additionally, one or more cocatalysts may be present. In another embodiment, the polyethylene composition can be produced via solution polymerization in a two-reactor system (e.g., a single loop reactor followed by an adiabatic continuous stirred tank reactor (CSTR)), wherein ethylene is polymerized in the presence of one or more catalyst systems and one or more comonomers. In yet another embodiment, the polyethylene component can be produced by solution polymerization in a single-reactor system, such as a single loop reactor system, wherein ethylene is polymerized in the presence of two catalyst systems and one or more comonomers.

[0063] catalyst system

[0064] Specific embodiments of a catalyst system that can be used in one or more embodiments to produce the polyethylene components described herein will now be described. It should be understood that the catalyst system of this disclosure may be embodied in different forms and should not be construed as limited to the specific embodiments set forth in this disclosure. Rather, the provision of embodiments makes this disclosure thorough and complete, and the embodiments will fully convey the scope of the subject matter to those skilled in the art. Without being bound by theory, it is believed that the catalyst system produces a mixture of a low-density component in the elution profile obtained by iCCD analysis within a temperature range of 40°C to 75°C and a high-density component in the elution profile obtained by iCCD analysis within a temperature range of 85°C to 110°C, wherein the low-density component can thus enable the polyethylene composition to reach a desired hot-tack initiation temperature, a heat-sealing initiation temperature, or both, and the high-density component can thus enable the polyethylene composition to achieve the desired adhesion.

[0065] The term "independently chosen" is used in this document to indicate R groups (such as R...). 1 R 2 R 3 R 4 and R 5 ) can be the same or different (e.g., R) 1 R 2 R 3 R 4 and R 5 Both can be substituted alkyl groups, or R 1 and R 2 It can be a substituted alkyl group and R 3(This can be aryl, etc.). The use of the singular form includes the use of the plural form, and vice versa (e.g., hexane solvent includes various hexanes). The named R group will generally have a structure recognized in the art as corresponding to the R group having that name. These definitions are intended to supplement and illustrate, rather than exclude, definitions known to those skilled in the art.

[0066] The term "procatalyst" refers to a compound that exhibits catalytic activity when combined with an activator. The term "activator" refers to a compound that chemically reacts with the procatalyst in a manner that converts the procatalyst into a catalytically active catalyst. As used herein, the terms "co-catalyst" and "activator" are interchangeable.

[0067] When used to describe certain carbon-containing chemical groups, the form is "(C x -C y The parenthetical expression “)” indicates that the unsubstituted form of the chemical group has x to y carbon atoms (inclusive). For example, (C1-C 40 Alkyl is an alkyl group having 1 to 40 carbon atoms in its unsubstituted form. In some embodiments and general structures, certain chemical groups may be substituted with one or more substituents such as RS. (C) x -C y The chemical groups defined in parentheses () are R S The substitution form can be based on any group R S The property contains more than y carbon atoms. For example, "exactly bound by a group R". S Replacement (C1-C) 40 ) alkyl, wherein R S The phenyl group (-C6H5) can contain 7 to 46 carbon atoms. Therefore, it is common practice to use the parenthetical phrase "(C6H5)" when referring to phenyl groups. x -C y The chemical group defined as ")" is substituent for one or more carbon atoms by one or more carbon-containing substituents R. S During substitution, both x and y are added with substituents R from all carbon atoms. s The minimum and maximum total number of carbon atoms in a chemical group are determined by the sum of the combinations of carbon atoms.

[0068] The term "substitution" means that at least one hydrogen atom (-H) bonded to the carbon atom or heteroatom corresponding to the unsubstituted compound or functional group is replaced by a substituent (e.g., R). S Substitution. The term "total substitution" means that each hydrogen atom (H) bonded to the carbon atom or heteroatom of the corresponding unsubstituted compound or functional group is replaced by a substituent (e.g., R). SSubstitution. The term "multi-substitution" means that at least two, but fewer than all, hydrogen atoms bonded to the corresponding unsubstituted carbon or heteroatom of a compound or functional group are replaced by substituents.

[0069] The term "-H" refers to a hydrogen or hydrogen group covalently bonded to another atom. "Hydrogen" and "-H" are interchangeable and, unless explicitly stated otherwise, refer to the same thing.

[0070] The term "(C1-C)" 40 "(C1-C) hydrocarbon group" refers to a hydrocarbon group having 1 to 40 carbon atoms, and the term "(C1-C) hydrocarbon group" is used in this context. 40 "Hydroalkylene" refers to a hydrocarbon diester having 1 to 40 carbon atoms, wherein each hydrocarbon group and each hydrocarbon diester is aromatic or non-aromatic, saturated or unsaturated, straight or branched, cyclic (including monocyclic and polycyclic, fused and non-fused polycyclic, including bicyclic; 3 or more carbon atoms) or acyclic, and is not substituted or surrounded by one or more R groups. S replace.

[0071] In this disclosure, (C) 1- C 40 The hydrocarbon group is independently unsubstituted or substituted (C1-C2). 40 )alkyl, (C3-C 40 )cycloalkyl, (C3-C 20 )cycloalkyl-(C1-C 20 )alkylene, (C6-C 40 ) aryl or (C6-C 20 )Aryl-(C 1- C 20 )alkylene. In some embodiments, the aforementioned (C1-C 40 Each hydrocarbon group in the hydrocarbon group has a maximum of 20 carbon atoms (i.e., (C1-C2)). 20 (hydrocarbon group), and in other embodiments, has up to 12 carbon atoms.

[0072] The term "(C1-C)" 40 alkyl and (C1-C) 18 "alkyl" refers to a saturated straight-chain or branched hydrocarbon group with 1 to 40 carbon atoms or 1 to 18 carbon atoms, which is unsubstituted or surrounded by one or more R groups. S Replacement. Unreplaced (C1-C) 40 Examples of alkyl groups are unsubstituted (C1-C1) alkyl groups. 20 )alkyl; unsubstituted (C1-C 10Alkyl; unsubstituted (C1-C5)alkyl; methyl; ethyl; 1-propyl; 2-propyl; 1-butyl; 2-butyl; 2-methylpropyl; 1,1-dimethylethyl; 1-pentyl; 1-hexyl; 1-heptyl; 1-nonyl; and 1-decyl. Substituted (C1-C5)alkyl 40 Examples of alkyl groups are substituted (C1-C2) 20 )alkyl, substituted (C1-C 10 )alkyl, trifluoromethyl and [C 45 Alkyl group. The term "[C]" 45 Alkyl (with square brackets) means that there are a maximum of 45 carbon atoms in the group (including substituents), and is, for example, enclosed by an R S Replacement (C) 27 --C 40 ) alkyl, which are (C1-C5) alkyl. Each (C1-C5) alkyl can be methyl, trifluoromethyl, ethyl, 1-propyl, 1-methylethyl or 1,1-dimethylethyl.

[0073] The term "(C6-C)" 40 "Aryl" refers to an unsubstituted or modified aryl group having 6 to 40 carbon atoms (one or more R groups). s A substituted monocyclic, bicyclic, or tricyclic aromatic hydrocarbon group, wherein at least 6 to 14 carbon atoms are aromatic ring carbon atoms, and the monocyclic, bicyclic, or tricyclic group comprises 1, 2, or 3 rings, respectively; wherein one ring is an aromatic ring, and the 2 or 3 rings are independently fused or non-fused rings, and at least one of the 2 or 3 rings is an aromatic ring. Unsubstituted (C6C) 40 An example of an aryl group is the unsubstituted (C6-C) 20 ) aryl; unsubstituted (C6-C 18 ) aryl; 2-(C1-C5)alkyl-phenyl; 2,4-bis(C1-C5)alkyl-phenyl; phenyl; fluorenyl; tetrahydrofluorenyl; dicyclopentadienylphenyl; hexahydrodicyclopentadienylphenyl; indene; dihydroindene; naphthyl; tetrahydronaphthyl; and phenanthrene. Substituted (C6-C 40 Examples of aryl groups are substituted (C1-C) 20 ) aryl; substituted (C6-C 18 )Aryl; 2,4-bis[(C 20 [alkyl]-phenyl; polyfluorophenyl; pentafluorophenyl; and fluorene-9-one-1-yl.

[0074] The term "(C3-C)" 40 "Cycloalkyl" refers to a saturated cyclic hydrocarbon group having 3 to 40 carbon atoms that is either unsubstituted or substituted with one or more Rs. Other cycloalkyl groups (e.g., (C x -C yCycloalkyl groups are defined in a similar manner as having x to y carbon atoms and being unsubstituted or substituted with one or more R groups. S Replaced. Unreplaced (C3-C) 40 Examples of cycloalkyl groups are unsubstituted (C3-C4) 20 )cycloalkyl, unsubstituted (C3-C 10 Cycloalkyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, and cyclodecyl. Substituted (C3-C) 40 Examples of cycloalkyl groups are substituted (C3-C4) 20 )cycloalkyl, substituted (C3-C 10 )cycloalkyl, cyclopentanone-2-yl and 1-fluorocyclohexyl.

[0075] (C1 C 40 Examples of alkylene groups include unsubstituted or substituted (C6-C) groups. 40 ()Asyl, (C3-C 40 )cycloalkylene and (C1-C 40 )alkylene (e.g., (C1-C 20 (alkylene). In some embodiments, the bimolecular group is located on the same carbon atom (e.g., -CH2-) or on adjacent carbon atoms (i.e., 1,2-bimolecular group), or separated by one, two, or more than two intercalary carbon atoms (e.g., 1,3-bimolecular group, 1,4-bimolecular group, etc.). Some bimolecular groups include α,ω-bimolecular groups. α,ω-bimolecular groups are bimolecular groups with the largest intercarbon backbone spacing between the group carbons. (C2-C) 20 Some examples of alkylene α,ω-bigroups include ethyl-1,2-diyl (i.e., -CH2CH2-), propan-1,3-diyl (i.e., -CH2CH2CH2-), and 2-methylpropan-1,3-diyl (i.e., -CH2CH(CH3)CH2-). (C6-C) 50 Some examples of arylene α,ω-dimethyl groups include phenyl-1,4-diyl, naphth-2,6-diyl, or naphth-3,7-diyl.

[0076] The term "(C1-C)" 40 "alkylene" means an unsubstituted or compounded alkylene with 1 to 40 carbon atoms. s Substituted saturated straight-chain or branched bigroups (i.e., the group is not on a ring atom). Unsubstituted (C1-C) 50 Examples of alkylene groups are unsubstituted (C1-C1) 20Alkylene groups, including unsubstituted -CH2CH2-, -(CH2)3-, -(CH2)4-, -(CH2)5-, -(CH2)6-, -(CH2)7-, -(CH2)8-, -CH2C*HCH3 and -(CH2)4C*(H)(CH3), where "C*" indicates the carbon atom from which a hydrogen atom is removed to form a secondary or tertiary alkyl group. Substituted (C1-C 50 Examples of alkylene groups are substituted (C1-C2) 20 Alkylene, -CF2-, -C(O)-, and -(CH2) 14 C(CH3)2(CH2)5- (i.e., 6,6-dimethyl-substituted n-1,20-eicosene). As previously stated, the two R... S They can form together (C1-C) 18 )alkylene, substituted (C1-C 50 Examples of alkylene groups also include 1,2-bis(methylene)cyclopentane, 1,2-bis(methylene)cyclohexane, 2,3-bis(methylene)-7,7-dimethyl-bicyclo[2.2.1]heptane and 2,3-bis(methylene)bicyclo[2.2.2]octene.

[0077] The term "(C3-C)" 40 "Cycloalkylene" refers to an unsubstituted or compounded alkylene oxide having 3 to 40 carbon atoms. S Substituted cyclic diradicals (i.e., radicals on ring atoms).

[0078] The term "heteroatom" refers to an atom other than hydrogen or carbon. Examples of heteroatoms include O, S, S(O), S(O)₂, and Si(R). C )2、P(R P ), N(R N -N=C(R) C )2、-Ge(R C )2- or -Si(R C )-, where each R C Each R N and each R P For unsubstituted (C1-C) 18 The term "heterohydrocarbon" refers to a molecule or molecular framework in which one or more carbon atoms are replaced by heteroatoms. The term "(C1-C)" is used in conjunction with the hydrocarbon group or -H. 40 "(C1-C4)" refers to a heterohydrocarbon group having 1 to 40 carbon atoms, and the term "(C1-C4)" is used in conjunction with the meaning of "(C1-C4)". 40"Heteroalkyl group" refers to a heteroalkyl bibase having 1 to 40 carbon atoms, and each heteroalkyl group has one or more heteroatoms. The bibase of the heteroalkyl group is located on a carbon atom or a heteroatom, and the bibase of the heteroalkyl group can be located on: (1) one or two carbon atoms, (2) one or two heteroatoms, or (3) a carbon atom and a heteroatom. Each (C1-C 50 ) heterohydrocarbon groups and (C1-C 50 Heteroalkyl groups can be unsubstituted or substituted with (one or more R groups). S Substituted, aromatic or non-aromatic, saturated or unsaturated, straight or branched, cyclic (including monocyclic and polycyclic, fused and non-fused polycyclic) or acyclic.

[0079] (C1-C 40 Heteroalkyl groups can be unsubstituted or substituted (C1-C2). 40 (heteroalkyl, (C1-C) 40 )hydrocarbon group -O-, (C1-C 40 )hydrocarbon group -S-, (C1-C 40 )hydrocarbon group -S(O)-, (C1-C 40 )hydrocarbon group -S(O)2-, (C1-C 40 )hydrocarbon-Si(RC)2-, (C1-C 40 )hydrocarbon-N(RN)-, (C1-C 40 )hydrocarbon group -P(RP)-, (C2-C 40 Heterocyclic alkyl groups, (C2-C 19 Heterocyclic alkyl-(C1-C) 20 )alkylene, (C3-C 20 )cycloalkyl-(C1-C 19 (Hypoalkylene, (C2-C) 19 Heterocyclic alkyl-(C1-C) 20 (Hypoalkylene, (C1-C) 40 () heteroaryl, (C1-C 19 ) heteroaryl-(C1-C 20 )alkylene, (C6-C 20 )aryl-(C1-C 19 (Hypoalkylene, or (C1-C) 19 ) heteroaryl-(C1-C 20 Heteroalkyl groups.

[0080] The term "(C3-C)" 40 "Heteroaryl" refers to an unsubstituted or substituted (by one or more R groups) compound with 4 to 40 total carbon atoms and 1 to 10 heteroatoms. SThe substituted monocyclic, bicyclic, or tricyclic heteroaryl group comprises one, two, or three rings, wherein the two or three rings are independently fused or unfused, and at least one of the two or three rings is heteroaromatic. Other heteroaryl groups (e.g., typically (C x -C y ) heteroaryl groups, such as (C4-C 12 (Heteroaryl) is defined in a similar manner as having x to y carbon atoms (such as 4 to 12 carbon atoms) and being unsubstituted or substituted by one or more R atoms. S Substituted. Monocyclic heteroaromatic hydrocarbon groups are 5- or 6-membered rings. A 5-membered ring has 5 minus h carbon atoms, where h is the number of heteroatoms and can be 1, 2, or 3; and each heteroatom can be O, S, N, or P. Examples of 5-membered heteroaromatic hydrocarbon groups are pyrrolo-1-yl; piperidin-2-yl; furan-3-yl; thiophene-2-yl; pyrazol-1-yl; isoxazol-2-yl; isothiazol-5-yl; imidazole-2-yl; oxazol-4-yl; thiazol-2-yl; 1,2,4-triazol-1-yl; 1,3,4-oxadiazol-2-yl; 1,3,4-thiadiazol-2-yl; tetrazol-1-yl; tetrazol-2-yl; and tetrazol-5-yl. A 6-membered ring has 6 minus h carbon atoms, where h is the number of heteroatoms and can be 1 or 2, and the heteroatom can be N or P. Examples of 6-membered ring heteroaromatic hydrocarbon groups are pyridin-2-yl; pyrimidin-2-yl; and pyrazin-2-yl. Bicyclic heteroaromatic hydrocarbon groups can be fused 5,6- or 6,6-cyclic systems. Examples of fused 5,6-cyclic bicyclic heteroaromatic hydrocarbon groups are indol-1-yl; and benzimidazol-1-yl. Examples of fused 6,6-cyclic bicyclic heteroaromatic hydrocarbon groups are quinoline-2-yl; and isoquinoline-1-yl. Bicyclic heteroaromatic hydrocarbon groups can be fused 5,6,5-cyclic systems; 5,6,6-cyclic systems; 6,5,6-cyclic systems; or 6,6,6-cyclic systems. An example of a fused 5,6,5-cyclic system is 1,7-dihydropyrrolo[3,2-f]indol-1-yl. An example of a fused 5,6,6-cyclic system is 1H-benzo[f]indol-1-yl. An example of a fused 6,5,6-cyclic system is 9H-carbazole-9-yl. An example of a fused 6,5,6-cyclic system is 9H-carbazole-9-yl. An example of a fused 6,6,6-cyclic system is acridine-9-yl.

[0081] The aforementioned heteroalkyl group may contain (C1-C1) 50 A saturated straight-chain or branched group containing one to 50 carbon atoms and one or more heteroatoms. Similarly, a heteroalkylene group can be a saturated straight-chain or branched bimolecular group containing 1 to 50 carbon atoms and one or more heteroatoms. Heteratoms as defined above can include Si(R) C 3. Ge(R) C 3. Si(R) C)2、Ge(R C )2、P(R P )2、P(R P ), N(R N )2、N(R N ), N, O, OR C , S, SR C S(O) and S(O)2, wherein each of the heteroalkyl and heteroalkylene groups is unsubstituted or is substituted by one or more R S replace.

[0082] Unreplaced (C2-C) 40 Examples of heterocyclic alkyl groups are unsubstituted (C2-C) 20 Heterocyclic alkyl groups, unsubstituted (C2-C) 10 Heterocyclic alkyl groups, aziridin-1-yl, oxacyclobut-2-yl, tetrahydrofuran-3-yl, pyrrolidine-1-yl, tetrahydrothiophene-S,S-dioxo-2-yl, morpholino-4-yl, 1,4-dioxane-2-yl, hexahydroacetane-4-yl, 3-oxacyclooctyl, 5-thiocyclononyl, and 2-azacyclodecyl.

[0083] The term "halogen atom" or "halogen" refers to a free radical of a fluorine (F), chlorine (Cl), bromine (Br), or iodine (I) atom. The term "halogen ion" refers to the anionic form of the following halogen atom: fluoride ion (F... - ), chloride ions (Cl) - ), bromide ions (Br) - ) or iodide ions (I - ).

[0084] The term "saturated" refers to the absence of carbon-carbon double bonds, carbon-carbon triple bonds, and (in heteroatom-containing groups) carbon-nitrogen, carbon-phosphorus, and carbon-silicon double bonds. In saturated chemical groups, the presence of one or more substituents R... S In the case of substitution, one or more double and / or triple bonds may or may not be present in the substituent R. S In Chinese, the term "unsaturated" means containing one or more carbon-carbon double bonds, carbon-carbon triple bonds, and (in heteroatom-containing groups) carbon-nitrogen, carbon-phosphorus, and carbon-silicon double bonds, excluding those that may exist in substituents R. S (If it exists) any such double bond in or that may exist in (hetero)aromatic rings (if it exists).

[0085] According to some embodiments, the catalyst system for producing the polyethylene composition comprises a metal-ligand complex according to formula (I):

[0086]

[0087] In formula (I), M is a metal selected from titanium, zirconium, or hafnium, in the form of an oxidation state of +2, +3, or +4; n is 0, 1, or 2; when n is 1, X is a monodentate or bidentate ligand; when n is 2, each X is a monodentate ligand and may be the same or different; the metal-ligand complex is electrically neutral overall; each Z is independently selected from -O-, -S-, -N(R-) N - or - P(R) P )-; L is (C1-C 40 ) hydrocarbon group or (C1-C 40 ) heterohydrocarbon group, of which (C1-C 40 The alkylene group has a portion of the main chain consisting of two Z groups in formula (I) with 1-carbon to 10-carbon atoms connected (to which L is bonded), or (C1-C 40 The heteroalkyl group has a portion of the main chain consisting of 1- to 10-atoms of two Z groups in formula (I), wherein (C1-C 40 The 1- to 10-atom connections of the heteroalkyl group to the 1- to 10 atoms of the main chain are each independently a carbon atom or a heteroatom, wherein each heteroatom is independently O, S, S(O), S(O)2, Si(R)2, or S(O)2. C )2、Ge(R C )2、P(R C ) or N(R C ), where each R C Independently is (C1-C 30 ) hydrocarbon group or (C1-C 30 ( ) heteroalkyl group; R1 and R8 are independently selected from the following groups: -H, (C1-C40)alkyl group, (C1-C 40 heterohydrocarbon group, -Si(R) C )3、-Ge(R C )3、-P(R P )2、-N(R N )2、-OR C -SR C、 -NO2, -CN, -CF3, R C S(O)-、R C S(O)2-、(R C )2C=N-、R C C(O)O-、R C OC(O)-, R C C(O)N(R N )-、(R N )2NC(O)-, halogens and groups having formula (II), (III) or (IV):

[0088]

[0089] In equations (II), (III), and (IV), R 31-35 R 41-48 or R 51-59 Each of them is independently selected from (C1-C) 40 ) hydrocarbon group, (C1-C 40 heterohydrocarbon group, -Si(R) C )3、-Ge(R C )3、-P(R P )2、-N(R N 2. -N=CHR C -OR C -SR C -NO2, -CN, -CF3, R C S(O)-、R C S(O)2-、(R C )2C=N-、R C C(O)O-、R C OC(O)-, R C C(O)N(R N )-、(R N )2NC(O)-, halogen or -H, with the constraint R 1 or R 8 At least one of them is a group having formula (II), formula (III) or formula (IV).

[0090] In equation (I), R 2-4 R 5-7 and R 9-16 Each of them is independently selected from (C1-C) 40 ) hydrocarbon group, (C1-C 40 heterohydrocarbon group, -Si(R) C )3、-Ge(R C )3、-P(R P )2、-N(R N 2. δ-N=CHR C -OR C -SR C -NO2, -CN, -CF3, R C S(O)-、R C S(O)2-、(R C )2C=N-、R C C(O)O-、R C OC(O)-, R C C(O)N(R N )-、(R C )2NC(O)-, halogens and -H.

[0091] In one exemplary embodiment using a dual-loop reactor, the primary catalyst used in the first loop is zirconium, [[2,2″′-[[bis[1-methylethyl)germanene]bis(methyleneoxy-κO)]bis[3″,5,5″-tris(1,1-dimethylethyl)-5′-octyl[1,1′∶3′,1″-terphenyl]-2′-olato-κO]](2-)]dimethyl-, having the chemical formula C 86 H 128 F2GeO4Zr and the following structure (V):

[0092]

[0093] In some embodiments, the polyethylene composition is formed using a first catalyst according to formula (I) in a first reactor and a Ziegler-Natta catalyst in a second reactor.

[0094] Ziegler-Natta catalysts suitable for use in a second reactor to prepare polyethylene compositions are typical supported Ziegler-type catalysts, particularly useful at high polymerization temperatures in solution processes. Examples of such compositions are those derived from organomagnesium compounds, alkyl halides, or aluminum halides or hydrogen chloride and transition metal compounds. Examples of such catalysts are described in U.S. Patents 4,612,300; 4,314,912; and 4,547,475, the teachings of which are incorporated herein by reference.

[0095] Particularly suitable organomagnesium compounds include, for example, hydrocarbon-soluble dialkyl magnesiums, such as dialkyl magnesiums and diaryl magnesiums. Exemplary suitable dialkyl magnesiums specifically include n-butyl-sec-butyl magnesium, diisopropyl magnesium, di-n-hexyl magnesium, isopropyl-n-butyl magnesium, ethyl-n-hexyl magnesium, ethyl-n-butyl magnesium, di-n-octyl magnesium, etc., wherein the alkyl group has 1 to 20 carbon atoms. Exemplary suitable diaryl magnesiums include diphenyl magnesium, dibenzyl magnesium, and xylyl magnesium. Suitable organomagnesium compounds include alkoxides and phenolates of alkyl magnesiums and aryl magnesiums, as well as halides of aryl magnesiums and alkyl magnesiums, more preferably halogen-free organomagnesium compounds.

[0096] Halogen sources include active nonmetallic halides, metallic halides, and hydrogen chloride. Suitable nonmetallic halides are represented by the formula R'X, where R' is hydrogen or an active monovalent organic group, and X is a halogen. Particularly suitable nonmetallic halides include, for example, hydrohalides and active organohalides such as tert-alkyl halides, allyl halides, benzyl halides, and other active hydrocarbon halides. "Active organohalides" refers to hydrocarbon halides containing unstable halogens, said unstable halogens being at least as reactive as sec-butyl chloride, i.e., readily lost to another compound, preferably as reactive as tert-butyl chloride. In addition to organic monohalides, it should be understood that organic dihalides, trihalides, and other polyhalides having the activity defined above may also be suitably employed. Examples of preferred active nonmetallic halides include hydrogen chloride, hydrogen bromide, tert-butyl chloride, tert-amyl bromide, allyl chloride, benzyl chloride, butenyl chloride, methylvinylcarbinyl chloride, α-phenylethyl bromide, diphenylmethyl chloride, etc. Hydrogen chloride, tert-butyl chloride, allyl chloride, and benzyl chloride are most preferred.

[0097] Suitable metal halides include those represented by the formula MRy-a Xa, where: M is a metal of Group IIB, IIIA, or IVA in Mendeleev's periodic table of elements; R is a monovalent organic group; X is a halogen; the value of y corresponds to the valence of M; and the value of "a" is from 1 to y. Preferred metal halides are those of the formula AlR. 3-a X a The aluminum halide, wherein each R is independently a hydrocarbon group, such as an alkyl group; X is a halogen; and a is a number from 1 to 3. Alkyl aluminum halides are most preferred, such as ethyl sesquichloride, diethylaluminum chloride, ethylaluminum dichloride, and diethylaluminum bromide, with ethylaluminum dichloride being particularly preferred. Alternatively, metal halides, such as aluminum trichloride or combinations of aluminum trichloride with alkyl aluminum halides or trialkylaluminum compounds, may be suitably used.

[0098] Any of the conventional Ziegler-Natta transition metal compounds can be usefully used as the transition metal component in the preparation of supported catalyst components. Typically, the transition metal component is a compound of a Group IVB, Group VB, or Group VIB metal. The transition metal component is usually represented by the following formula: TrX' 4-q (OR1)q、TrX' 4-q And (R2)q.

[0099] Tr is a metal of group IVB, group VB or group VIB, preferably a metal of group IVB or group VB, preferably titanium, vanadium or zirconium; q is 0 or a number equal to or less than 4; X' is a halogen, and R1 is an alkyl group, aryl group or cycloalkyl group having 1 to 20 carbon atoms; and R2 is an alkyl group, aryl group, arylalkyl group, substituted aralkyl group, etc.

[0100] Aryl, aralkyl, and substituted aralkyl groups contain 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms. When the transition metal compound contains a hydrocarbon group R2, the hydrocarbon group is alkyl, cycloalkyl, aryl, or aralkyl, and the hydrocarbon group will preferably not contain a hydrogen atom at the β-to-metal carbon bond position. Illustrative but non-limiting examples of aralkyl groups are methyl, neopentyl, 2,2-dimethylbutyl, and 2,2-dimethylhexyl; aryl groups, such as benzyl; and cycloalkyl groups, such as 1-norbornyl. Mixtures of these transition metal compounds may be used if desired.

[0101] Illustrative examples of transition metal compounds include TiCl4, TiBr4, Ti(OC2H5)3Cl, Ti(OC2H5)Cl3, Ti(OC4H9)3Cl, and Ti(OC3H7)2Cl. .2 Ti(OC6H) 13 )2Cl2、Ti(OC8H 17 )2Br2 and Ti(OC 12 H 25 Vanadium compounds include ZrCl4, VOCl3, VO(OC2H5)3, and VO(OC4H9)3. Illustrative examples of zirconium compounds include ZrCl4, ZrCl3(OC2H5), ZrCl2(OC2H5)2, ZrCl(OC2H5)3, Zr(OC2H5)4, ZrCl3(OC4H9), ZrCl2(OC4H9)2, and ZrCl(OC4H9)3.

[0102] Inorganic oxide supports can be used in the preparation of catalysts, and the supports can be any particulate oxide or a mixture of oxides that have been thermally or chemically dehydrated to be substantially free of adsorbed water. See U.S. Patents 4,612,300, 4,314,912, and 4,547,475, the teachings of which are incorporated herein by reference.

[0103] co-catalyst components

[0104] Catalytic activity can be achieved by any technique known in the art for activating metal-based catalysts for olefin polymerization reactions, including metal-ligand complexes of formula (I). For example, a system comprising a metal-ligand complex of formula (I) can be made catalytically active by contacting the complex with an activating cocatalyst or by combining the complex with an activating cocatalyst. Activating cocatalysts suitable for this document include alkylaluminum; polymeric or oligomeric aluminum oxanes (also known as aluminum oxanes); neutral Lewis acids; and non-polymeric, non-coordinated, ion-forming compounds (including those used under oxidizing conditions). A suitable activation technique is bulk electrolysis. Combinations of one or more of the aforementioned activating cocatalysts and techniques are also contemplated. The term "alkylaluminum" means dihydrogenated monoalkylaluminum or dihalogenated monoalkylaluminum, hydrogenated dialkylaluminum or halodialkylaluminum, or trialkylaluminum. Examples of polymeric or oligomeric aluminum oxanes include methylaluminoxane, methylaluminoxane modified with triisobutylaluminum, and isobutylaluminoxane.

[0105] Lewis acid activators (co-catalysts) contain one to three (C1-C1) atoms as described herein. 20 A Group 13 metal compound with a hydrocarbon substituent. In one embodiment, the Group 13 metal compound is a tri((C1-C) group 13 metal compound. 20 ()hydrocarbon-substituted aluminum or tri((C1-C) 20 (Hydrocarbon)-boron compounds. In other embodiments, the Group 13 metal compound is a tri(hydrocarbon)-substituted aluminum, tri((C1-C)-boron compound. 20 )hydro-boron compounds, tri((C1--C 10 Alkyl aluminum, tri((C6-C) 18 (Aryl)boron compounds and their halogenated (including perhalogenated) derivatives. In other embodiments, the Group 13 metal compound is tris(fluorosubstituted phenyl)borane or tris(pentafluorophenyl)borane. In some embodiments, the activation cocatalyst is tris((C1-C)borane. 20 ) hydrocarbon borates (e.g., triphenylmethyltetrafluoroborate) or tri((C1-C 20 )hydro-based)ammonium tetra((C1-C 20 (e.g., bis(octadecyl)methylammonium tetra(pentafluorophenyl)borane). As used herein, the term "ammonium" refers to a nitrogen cation that is ((C1-C2) 20 )hydrocarbon group)4N + 、((C1-C 20 )hydrocarbon group)3N(H) + 、((C1-C 20 )hydrocarbon group)2N(H)2 + (C1-C) 20 )hydrocarbon group 3 + or N(H)4 +Where there are two or more (C1-C) 20 When there are hydrocarbon groups, they can be the same or different.

[0106] The combination of neutral Lewis acid activators (co-catalysts) includes tris((C1-C4)alkyl)aluminum and tri((C6-C4)halogenated tris((C6-C4)alkyl)aluminum. 18 Mixtures of arylborane compounds, particularly tris(pentafluorophenyl)borane. Other embodiments are combinations of such neutral Lewis acid mixtures with polymeric or oligomeric aluminum oxanes, and combinations of single neutral Lewis acids (especially tris(pentafluorophenyl)borane) with polymeric or oligomeric aluminum oxanes.

[0107] The metal-ligand complex catalyst system comprising formula (I) can be activated by combination with one or more cocatalysts (e.g., cation-forming cocatalysts, strong Lewis acids, or combinations thereof) to form an active catalyst composition. Suitable activation cocatalysts comprise polymeric or oligomeric aluminum oxanes (especially methylaluminoxanes) and inert, compatible, noncoordinate, ionic compounds. Exemplary suitable cocatalysts include, but are not limited to: modified methylaluminoxane (MMAO), bis(hydrogenated tallow alkyl)methyltetra(pentafluorophenyl)boronic acid (1-)amine, and combinations thereof.

[0108] In some embodiments, one or more of the aforementioned activating cocatalysts are used in combination with each other. Particularly preferred combinations are mixtures of tris((C1-C4)alkyl)aluminum, tris((C1-C4)alkyl)borane, or ammonium borate with oligomeric or polymeric aluminum oxane compounds. The ratio of the total molar number of one or more metal-ligand complexes of formula (I) to the total molar number of one or more activating cocatalysts in the activating cocatalyst is from 1:10,000 to 100:1. In some embodiments, the ratio is at least 1:5000, in some other embodiments at least 1:1000; and 10:1 or less, and in some other embodiments 1:1 or less. When an aluminum oxane is used alone as an activating cocatalyst, preferably, the molar number of aluminum used is at least 10 times the molar number of the metal-ligand complex of formula (I). For example, when tris(pentafluorophenyl)borane is used alone as an activation cocatalyst, the ratio of the molar amount of tris(pentafluorophenyl)borane to the total molar amount of one or more metal-ligand complexes of formula (I) is 0.5:1 to 10:1, 1:1 to 6:1, or 1:1 to 5:1. The remaining activation cocatalyst is usually used in a molar amount approximately equal to the total molar amount of one or more metal-ligand complexes of formula (I).

[0109] membrane

[0110] In some embodiments, the embodiments disclosed herein relate to films formed from any of the polyethylene compositions disclosed herein. In some embodiments, the film may be a blown film or a cast film. In some embodiments, the film may be an extruded coated film. In some embodiments, the film may be a single-layer film. In some embodiments, the film may be a multilayer film. In some embodiments of a multilayer film including the polyethylene compositions disclosed herein, the multilayer film may include the polyethylene compositions disclosed herein in the surface layer and / or inner layer. In some embodiments, the polyethylene compositions disclosed herein may be used to provide a sealant layer in a multilayer film. For example, the polyethylene compositions disclosed herein may be located in the outer layer of a multilayer film formed by co-extrusion of a blown film or a cast film process. The sealant layer may provide a heat-sealable surface. As used herein, a heat-sealable surface is a surface that allows the surface of the film to be heat-sealed to another surface of the same film or the surface of another film or substrate.

[0111] In one or more embodiments, the polyethylene compositions disclosed herein may be blended with other polymers, such as other polyethylenes or even other non-polyethylene-based polymers. For example, the polyethylene compositions disclosed herein may be blended with conventional polyethylene compositions known to those skilled in the art, such as, but not limited to, LDPE, LLDPE, HDPE, MDPE and / or polyethylene-based plastomers or elastomers.

[0112] The amount of polyethylene composition used in the membrane of this embodiment can depend on many factors, including, for example, whether the membrane is a single-layer or multi-layer membrane, the other layers in the membrane (if it is a multi-layer membrane), the end use of the membrane, etc.

[0113] The membranes disclosed herein can have a variety of thicknesses. The thickness of the membrane depends on many factors, including, for example, whether the membrane is a single-layer or multilayer membrane, the other layers in the membrane (if it is a multilayer membrane), the desired properties of the membrane, the application in which the membrane is ultimately used, the equipment available for manufacturing the membrane, etc. In some embodiments, the membranes of this disclosure have a thickness of up to 10 mils. For example, the membrane can have a thickness from a lower limit of 0.25 mils, 0.5 mils, 0.7 mils, 1.0 mils, 1.75 mils, or 2.0 mils to an upper limit of 4.0 mils, 6.0 mils, 8.0 mils, or 10 mils. In the embodiments, the thickness of the membrane can be 0.25 mil to 2.0 mil, 0.25 mil to 1.75 mil, 0.25 mil to 1.0 mil, 0.25 mil to 0.7 mil, 0.25 mil to 0.5 mil, 0.5 mil to 2.0 mil, 0.5 mil to 1.75 mil, 0.5 mil to 1.0 mil, 0.5 mil to 0.7 mil, 0.7 mil to 2.0 mil, 0.7 mil to 1.75 mil, 0.7 mil to 1.0 mil, 1.0 mil to 2.0 mil, 1.0 mil to 1.75 mil, 1.75 mil to 2.0 mil, or any combination of these ranges.

[0114] In embodiments where the membrane includes a multilayer membrane, the number of layers in the membrane can depend on many factors, including, for example, the desired properties of the membrane, the desired thickness of the membrane, the content of other layers in the membrane, the end use of the membrane, the equipment available for manufacturing the membrane, etc. In various embodiments, the multilayer blown membrane may include up to 2, 3, 4, 5, 6, 7, 8, 9, 10, or 11 layers.

[0115] In some embodiments, the polyethylene composition may be used in a membrane with more than one layer. Other layers within the multilayer membrane of this disclosure may, in various embodiments, comprise polymers selected from: the polyethylene compositions disclosed herein, LLDPE, VLDPE (very low density polyethylene), MDPE, LDPE, HDPE, HMWHDPE (high molecular weight HDPE), propylene-based polymers, polyolefin plastomers (POP), polyolefin elastomers (POE), olefin block copolymers (OBC), ethylene vinyl acetate, ethylene acrylate, ethylene methacrylate, ethylene methyl acrylate, ethylene ethyl acrylate, ethylene butyl acrylate, isobutylene, maleic anhydride-grafted polyolefins, ionomers of any of the foregoing, or combinations thereof. In some embodiments, the multilayer membrane of this disclosure may include one or more connecting layers known to those skilled in the art.

[0116] In other embodiments of the polyolefin film described herein, additional layers may be adhered to, for example, a polyethylene film via an adhesive layer (sometimes in addition to the barrier layer). The adhesive layer can be used to adhere layers of different materials. For example, a barrier layer comprising an ethylene-vinyl alcohol copolymer (EVOH) may be adhered to a polyethylene material via an adhesive layer (i.e., an adhesive layer comprising maleic anhydride-grafted polyethylene). For example, depending on the application, the polyolefin film may further include other layers typically included in a multilayer structure, including, for example, other barrier layers, structural or strength layers, sealant layers, other adhesive layers, other polyethylene layers, polypropylene layers, etc. In another embodiment, a printing layer may be included to display product details and other packaging information in various colors; this printing layer may be an ink layer applied to the film.

[0117] It should be understood that any of the aforementioned layers may further include one or more additives known to those skilled in the art, such as antioxidants, UV stabilizers, heat stabilizers, slip agents, antiblocking agents, pigments or colorants, processing aids, crosslinking catalysts, flame retardants, fillers, and foaming agents. In some embodiments, the polyethylene composition contains up to 5% by weight of such additional additives. This document includes and discloses all individual values ​​and sub-ranges from 0% by weight to 5% by weight; for example, the total amount of additives in the polymer blend may range from the lower limit of 0% by weight, 0.5% by weight, 1% by weight, 1.5% by weight, 2% by weight, or 2.5% by weight to the upper limit of 1.5% by weight, 2% by weight, 2.5% by weight, 3% by weight, 3.5% by weight, 4% by weight, 4.5% by weight, or 5% by weight. In the embodiments, the total amount of additives in the polymer blend can be from 0 wt% to 5 wt%, 0 wt% to 4.5 wt%, 0 wt% to 4 wt%, 0 wt% to 3.5 wt%, 0 wt% to 3 wt%, 0 wt% to 2.5 wt%, 0 wt% to 2 wt%, 0 wt% to 1.5 wt%, 0 wt% to 1 wt%, 0 wt% to 0.5 wt%, 0.5 wt% to 5 wt%, 0.5 wt% to 4.5 wt%, 0.5 wt% to 4 wt%, 0 0.5% to 3.5% by weight, 0.5% to 3% by weight, 0.5% to 2.5% by weight, 0.5% to 2% by weight, 0.5% to 1.5% by weight, 0.5% to 1% by weight, 1% to 5% by weight, 1% to 4.5% by weight, 1% to 4% by weight, 1% to 3.5% by weight, 1% to 3% by weight, 1% to 2.5% by weight, 1% to 2% by weight, 1% to 1.5% by weight, 1.5% to 5 wt%, 1.5 wt% to 4.5 wt%, 1.5 wt% to 4 wt%, 1.5 wt% to 3.5 wt%, 1.5 wt% to 3 wt%, 1.5 wt% to 2.5 wt%, 1.5 wt% to 2 wt%, 2 wt% to 5 wt%, 2 wt% to 4.5 wt%, 2 wt% to 4 wt%, 2 wt% to 3.5 wt%, 2 wt% to 3 wt%, 2 wt% to 2.5 wt%, 2.5 wt% to 5 wt%, 2.5 wt% to 4.5 wt% The range is 1%, 2.5% to 4% by weight, 2.5% to 3.5% by weight, 2.5% to 3% by weight, 3% to 5% by weight, 3% to 4.5% by weight, 3% to 4% by weight, 3% to 3.5% by weight, 3.5% to 5% by weight, 3.5% to 4.5% by weight, 3.5% to 4% by weight, 4% to 5% by weight, 4% to 4.5% by weight or 4.5% to 5% by weight, or any combination of these ranges.

[0118] According to some embodiments, the polyethylene compositions disclosed herein can be incorporated into multilayer films and articles, which are primarily (if not substantially or entirely) composed of polyolefins or more preferably of polyethylene, to provide films and articles that are easier to recycle. The polyethylene polymers disclosed herein are particularly advantageous in validating films in which the membrane is primarily formed of polyethylene. For example, in addition to other advantages that can be provided by using such polymers, single-layer or multilayer films in which the membrane primarily comprises polyethylene can have improved recyclability characteristics. In some embodiments, the membrane contains 90% by weight or more polyethylene by total weight. In other embodiments, the membrane contains 91% by weight or more, 92% by weight or more, 93% by weight or more, 94% by weight or more, 95% by weight or more, 96% by weight or more, 97% by weight or more, 98% by weight or more, or 99% by weight or more polyethylene by total weight.

[0119] In some embodiments, a membrane comprising a layer formed from the polyethylene compositions disclosed herein may be laminated onto another membrane substrate. The substrate may include membranes comprising polyester, nylon, polypropylene, polyethylene, and combinations thereof. For preferred recyclable substrates, biaxially oriented polyethylene (BOPE) substrates, longitudinally oriented polyethylene (MDO) substrates, or co-extruded polyethylene films may be included in the laminated structure.

[0120] In some embodiments, the films of this disclosure may be corona-treated and / or printed (e.g., reverse or surface printing) using techniques known to those skilled in the art.

[0121] In some embodiments, the membranes of this disclosure may be uniaxial (e.g., longitudinally) or biaxially oriented using techniques known to those skilled in the art.

[0122] In embodiments, when measured according to the methods described below, films comprising the polyethylene compositions of this disclosure may have an adhesive force of less than 40 mn / inch or less than 35 mn / inch. Similar methods can be used to observe the adhesive forces of single-layer and other multilayer films. In embodiments of single-layer and other multilayer films, their adhesive forces are comparable to or less than those of comparative films not utilizing the polyethylene compositions described herein.

[0123] Products

[0124] Embodiments of this disclosure also relate to articles, such as packaging, formed or incorporated from or incorporated with the polyethylene compositions of this disclosure (i.e., by incorporating a film with a polyethylene composition of this disclosure). Such packaging may be formed from any of the polyethylene compositions of this disclosure (or by incorporating a film with a polyethylene-based composition of this disclosure). Such packaging formed from any polyethylene composition of this disclosure may be sealed by various sealing methods known in the art, such as heat sealing.

[0125] Examples of such articles may include flexible packaging, bags, stand-up pouches, and pre-made packaging or bags. In some embodiments, the multilayer films or laminates of this disclosure may be used for food packaging. Examples of foods that may be contained in such packaging include meats, cheeses, grains, nuts, snacks, juices, sauces, etc. Based on the teachings herein and the specific purpose of the packaging (e.g., the type of food, the quantity of food, etc.), such packaging may be formed using techniques known to those skilled in the art.

[0126] Low heat-sealing initiation temperatures (such as those provided by the polyethylene compositions of the present invention) can be particularly desirable for automated packaging systems in which the articles being packaged are loaded into the packaging during manufacturing. Lower heat-sealing initiation temperatures can be advantageous in increasing packaging productivity by minimizing the time and energy required to heat and cool the sealant. In cases where recyclable polyethylene packaging has an inner sealant layer that seals at a temperature significantly lower than the outer polyethylene layer, heat-sealing packaging can be manufactured over a wider temperature range, often referred to as the packaging heat-sealing window. Some examples of such automated packaging equipment are referred to as vertical form-fill-seal (VFFS) machines or horizontal form-fill-seal (HFFS) machines.

[0127] Test methods

[0128] Unless otherwise indicated herein, the following analytical methods are used to describe various aspects of this disclosure:

[0129] Melt Flow Index

[0130] The melt index I2 (or I2) and I of the polymer sample 10 (Or I10) Measured according to ASTM D-1238 at 190°C and under loads of 2.16 kg and 10 kg respectively. The values ​​are reported in g / 10 min.

[0131] density

[0132] Samples for density measurement are prepared according to ASTM D4703. According to ASTM D792, Method B involves measuring the sample within one hour of pressing it.

[0133] Creep zero-shear viscosity measurement method

[0134] Zero shear viscosity was obtained through creep testing on an AR-G2 stress-controlled rheometer (TA Instruments; New Castle, Del) using 25 mm diameter parallel plates at 190 °C. The rheometer oven was set to the test temperature for at least 30 minutes before zeroing the fixture. At the test temperature, a compression-molded sample disc was inserted between the plates and allowed to equilibrate for 5 minutes. The upper plate was then lowered to 50 μm above the desired test gap (1.5 mm). Any excess material was trimmed off, and the upper plate was lowered to the required gap. Measurements were performed under nitrogen purging at a flow rate of 5 L / min. The default creep time was set to 2 hours.

[0135] A constant low shear stress of 20 Pa was applied to all samples to ensure that the steady-state shear rate was low enough to fall within the Newtonian region. For the samples in this study, the obtained steady-state shear rates were within 10 Pa. -3 Up to 10 -4 s -1 Within the range of [value missing]. Steady state was determined by linear regression of all data points in the last 10% time window of the log(J(t)) versus log(t) curve, where J(t) is the creep compliance and t is the creep time. If the slope of the linear regression was greater than 0.97, steady state was considered reached, and the creep test was stopped. In all cases of this study, the slope satisfied the stated criterion within 2 hours. The steady-state shear rate was determined by the slope of the linear regression of all data points in the last 10% time window of the ε versus t plot, where ε is the strain. Zero-shear viscosity was determined by the ratio of applied stress to the steady-state shear rate.

[0136] To determine whether a sample degraded during creep testing, the same sample was subjected to small-amplitude oscillatory shear tests ranging from 0.1 to 100 radians / second before and after the creep test. The complex viscosity values ​​of the two tests were compared. If the difference in viscosity values ​​was greater than 5% at 0.1 radians / second, the sample was considered to have degraded during creep testing, and the results were discarded.

[0137] Gel permeation chromatography (GPC)

[0138] The chromatographic system consisted of a PolymerChar GPC-IR (Valencia, Spain) high-temperature GPC chromatograph equipped with an internal IR5 infrared detector (IR5). The autosampler oven chamber was set to 160°C, and the column chamber to 150°C. The columns used were four Agilent "Mixed A" 30cm 20µm linear mixed-bed columns and a 20µm pre-column. The chromatographic solvent used was 1,2,4-trichlorobenzene containing 200ppm of butylated hydroxytoluene (BHT). The solvent source was nitrogen injection. The injection volume was 200µL, and the flow rate was 1.0mL / min.

[0139] The GPC column assembly was calibrated using 21 polystyrene standards with narrow molecular weight distributions, ranging from 580 to 8,400,000, arranged in six “cocktail” mixtures, with individual molecular weights spaced at least tenfold apart. The standards were purchased from Agilent Technologies. For molecular weights equal to or greater than 1,000,000, 0.025 g of polystyrene standard was prepared in 50 mL of solvent; for molecular weights less than 1,000,000, 0.05 g of polystyrene standard was prepared in 50 mL of solvent. The polystyrene standards were dissolved at 80°C and gently stirred for 30 minutes. The peak molecular weights of the polystyrene standards were converted to polyethylene molecular weights using Equation 1 (as described in Williams and Ward, *Journal of Polymer Science and Polymer Letters*, 6, 621 (1968)).

[0140] M 聚乙烯 =A×(M) 聚苯乙烯 ) B (Equation 1)

[0141] Where M is the molecular weight, A has a value of 0.4315, and B equals 1.0.

[0142] A fifth-order polynomial was used to fit the calibration point for the corresponding polyethylene equivalent. A small adjustment to A (approximately 0.375 to 0.445) was made to correct for column resolution and band broadening effects, resulting in linear homopolymer polyethylene standards at 120,000 Mw.

[0143] Plate counting was performed on the GPC column assembly using decane (prepared as 0.04 g in 50 mL TCB and dissolved under slow stirring for 20 min). Plate counts (Equation 2) and symmetry (Equation 3) were measured at 200 μL injections according to the following equations:

[0144]

[0145] Where RV is the retention volume in milliliters, peak width is in milliliters, peak maximum is the maximum height of the peak, and 1 / 2 height is 1 / 2 the height of the peak maximum.

[0146]

[0147] Where RV is the retention volume in milliliters, and peak width is in milliliters, peak maximum is the position of the peak value, one-tenth height is 1 / 10 of the height of the peak maximum, and a subsequent peak refers to the tail of a peak whose retention volume is later than the peak maximum, while a preceding peak refers to the front of a peak whose retention volume is earlier than the peak maximum. The plate count of the chromatographic system should be greater than 18,000, and the symmetry should be between 0.98 and 1.22.

[0148] Samples were prepared semi-automatically using PolymerChar "Instrument Control" software, with a target sample weight of 2 mg / ml. Solvent (containing 200 ppm BHT) was added to a pre-bubbled, diaphragm-capped vial using a PolymerChar high-temperature autosampler. The sample was then dissolved at 160°C for 2 hours with "low-speed" shaking.

[0149] Based on the GPC results, using the internal IR5 detector (measurement channel) of the PolymerChar GPC-IR chromatograph, according to Equations 4-6, the PolymerChar GPCOne was used. TM The software performs baseline subtraction on the IR chromatograms at each equidistant data collection point (i) and analyzes the polyethylene equivalent molecular weight (Mn) obtained from the calibration curve of the narrow standard at point (i) according to Equation 1. (GPC) Mw (GPC) and Mz (GPC) The calculation.

[0150]

[0151]

[0152]

[0153] To monitor deviations over time, a flow rate marker (decane) was introduced into each sample via a micropump controlled by a PolymerChar GPC-IR system. This flow rate marker (FM) was used to linearly correct the pump flow rate (nominal flow rate) for each sample by comparing the RV (RV(FM sample)) of the corresponding decane peak within the sample with the RV (RV(FM calibrated)) of the decane peak within the narrow standard calibration. It was then assumed that any variation in the decane marker peak time was linearly related to the flow rate (effective flow rate) throughout the run. To achieve the highest accuracy in the RV measurement of the flow marker peak, a least-squares fitting procedure was used to fit the peak values ​​of the flow marker concentration chromatogram to a quadratic equation. The first derivative of the quadratic equation was then used to solve for the true peak position. After calibration based on the flow marker peak, the effective flow rate (relative to the narrow standard calibration) was calculated according to Equation 7. (via PolymerChar GPCOne) TM The software processes the flow marker peaks. Acceptable flow rate correction ensures that the effective flow rate is within + / - 0.5% of the nominal flow rate.

[0154] Flow rate (effective) = Flow rate (nominal) * (RV (FM calibrated) / RV (FM sample)) (Equation 7)

[0155] Molecularly weighted comonomer distribution index (MWCDI)

[0156] The GPC-IR high-temperature chromatography system from Perimocha (Valencia, Spain) was equipped with a precision detector (Amherst, MA), a Model 2040 2-angle laser scattering detector, an IR5 infrared detector (GPC-IR), and a 4-capillary viscometer, all from Perimocha. A 15-degree angle of the light scattering detector was used for computational purposes. Data collection was performed using Perimocha's Instrument Control software and data acquisition interface. The system was equipped with an online solvent degassing unit and pumping system from Agilent Technologies (Santa Clara, CA).

[0157] The injection temperature was controlled at 150°C. The columns used were four 20-micron "Mixed-A" light scattering columns from a polymer laboratory (Shropshire, UK). The solvent was 1,2,4-trichlorobenzene. The sample was prepared at a concentration of "0.1 g polymer in 50 mL of solvent". Both the chromatographic solvent and the sample preparation solvent each contained "200 ppm butylated hydroxytoluene (BHT)". Both solvent sources were bubbled with nitrogen. The ethylene-based polymer sample was gently stirred at 160°C for three hours. The injection volume was "200 μL", and the flow rate was "1 mL / min".

[0158] The GPC column setup was calibrated using 21 polystyrene standards with narrow molecular weight distributions, ranging from 580 g / mol to 8,400,000 g / mol. These standards were arranged in six "mixture" solutions, with at least ten-fold spacing between individual molecular weights. The standards were purchased from Polymer Laboratories (Shropshire, UK). The polystyrene standards were prepared as follows: for molecular weights equal to or greater than 1,000,000 g / mol, 0.025 g in 50 mL of solvent; and for molecular weights less than 1,000,000 g / mol, 0.050 g in 50 mL of solvent. The polystyrene standards were dissolved by gentle stirring at 80°C for 30 minutes. The narrow standard mixtures were run first, minimizing degradation in descending order of molecular weight component. The peak molecular weight of polystyrene standards was converted to polyethylene molecular weight using Equation 1 (as described by Williams and Ward, J. Polym. Sci., Polym. Let.), 6, 621 (1968):

[0159] Where M is the molecular weight, A is approximately 0.40, and B equals 1.0. The value of A is adjusted between 0.375 and 0.445 (depending on the specific column setup efficiency) so that the weight-average molecular weight of NBS 1475A (NIST) linear polyethylene corresponds to 52,000 g / mol as calculated by the following equation:

[0160]

[0161]

[0162] In Equations 8 and 9, RV is the column retention volume collected at “1 point / second” (linearly spaced). IR is the IR detector signal from the measurement channel of the GPC instrument minus the baseline, in volts, and MPE is the polyethylene equivalent in MW determined from Equation 1 above. Data calculations were performed using “GPC One Software (version 2.013H)” from Perimocha.

[0163] IR5 detector ratio calibration was performed using at least ten ethylene-based polymer standards (polyethylene homopolymers and ethylene / octene copolymers; narrow molecular weight distribution and uniform comonomer distribution) with known short-chain branching (SCB) frequencies (measured by the 13C NMR method discussed above). These standards ranged from approximately 50 SCBs / 1000 total C in homopolymers (0 SCB / 1000 total C), where total C = carbon in the main chain + carbon in the branches. The weight-average molecular weight of each standard was from 36,000 g / mol to 126,000 g / mol, as determined by the GPC-LALS processing method described above. The molecular weight distribution (Mw / Mn) of each standard was from 2.0 to 2.5, as determined by the GPC-LALS processing method described above. The three polymer characteristics of the SCB standards are shown in Table A.

[0164] Table A: "SCB" Standard Products

[0165]

[0166]

[0167] For each of the “SCB” standards, calculate the “IR5 area ratio (or “IR5 methyl channel area / IR5 measurement channel area”) of the “area response of the IR5 methyl channel sensor minus the baseline” to the “area response of the IR5 measurement channel sensor minus the baseline” (as per standard filters and filter wheels supplied by PolymerChar: part number IR5_FWM01 included as part of the GPC-IR instrument). The linear fit of the SCB frequency to the “IR5 area ratio” is constructed in the form of Equation 10:

[0168] SCB / 1000 total C = A0 + [A1 x (IR5 methyl channel area / IR5 measurement channel area)] (Equation 10)

[0169] Where A0 is the zero intercept of "SCB / 1000 total C" under "IR5 area ratio", and A1 is the slope of "SCB / 1000 total C" with respect to "IR5 area ratio" and indicates that SCB / 1000 total C increases with "IR5 area ratio".

[0170] A series of linear subtractions of baseline chromatographic height from the chromatograms generated by the IR5 methyl channel sensor were established as a function of column elution volume to produce baseline-corrected chromatograms (methyl channel). A series of linear subtractions of baseline chromatographic height from the chromatograms generated by the IR5 measurement channel were also established as a function of column elution volume to produce baseline-corrected chromatograms (measurement channel).

[0171] At each column elution volume index (each equally spaced index representing 1 data point per second at 1 mL / min elution) at both ends of the sample integration limit, calculate the "IR5 height ratio" of the "baseline-corrected chromatogram (methyl channel)" versus the "baseline-corrected chromatogram (measurement channel)". Multiply the "IR5 height ratio" by a coefficient A1 and add a coefficient A0 to this result to produce the predicted SCB frequency of the sample. Convert the result to comonomer molar percentage in Equation 11 as follows:

[0172] Comonomer molar percentage = {SCBf / [SCBf+((1000-SCBf*comonomer length) / 2)]}*100 (Equation 11)

[0173] Where “SCBf” is the SCB per 1000 total C, and “comonomer length” = 8 (for octene), 6 (for hexene), etc.

[0174] Each elution volume index was converted to a molecular weight value (Mwi) using the method of Williams and Ward (as described above; Equation 1). The "comonomer molar percentage (y-axis)" was plotted as a function of Log(Mwi), and the slope between long Mwi values ​​of 15,000 g / mol and 150,000 g / mol was calculated (end-group corrections at the chain ends were omitted for this calculation). An EXCEL linear regression was used to calculate the slope between Mwi values ​​from 15,000 to 150,000 g / mol (and including the ends). This slope was defined as the molecularly weighted comonomer distribution index (MWCDI = Molecularly Weighted Comonomer Distribution Index).

[0175] An Improved Method for iCCD Comonomer Content Distribution Analysis

[0176] An improved method for comonomer content analysis (iCCD) was developed in 2015 (Cong and Parrott et al., WO2017040127A1). iCCD tests were performed using a Crystallization Elution Fractionation (CEF) instrument (Perimocha, Spain) equipped with an IR-5 detector (PolymerChar, Spain) and a two-corner light scattering detector model 2040 (Precision Detectors, now Agilent Technologies). A protective column filled with 20-27 micron glass (MoSCi Corporation, USA) was installed just before the IR-5 detector in the detector oven. o-Dichlorobenzene (ODCB, 99% anhydrous or industrial grade) was used. The results were obtained from EMD. Chemicals obtained silica gel 40 (particle size 0.2–0.5 mm, catalog number 10181-3) (previously used as a solvent for drying ODCB). The CEF instrument was equipped with an autosampler with N2 sweep capability. ODCB was bubbled with dry nitrogen (N2) for one hour before use. Sample preparation was performed at 160°C with shaking at a concentration of 4 mg / mL (unless otherwise specified) using the autosampler for 1 hour. The injection volume was 300 μL. The iCCD temperature profile was as follows: crystallization from 105°C to 30°C at 3°C / min, thermal equilibration at 30°C for 2 minutes (including a 2-minute elution time for the soluble fraction), and elution from 30°C to 140°C at 3°C / min. The flow rate during crystallization was 0.0 mL / min. The flow rate during elution was 0.50 mL / min. Data was collected at a rate of one data point per second.

[0177] An iCCD column was filled with gold-plated nickel particles (Bright7GNM8-NiS, Nippon Chemical Industrial Co.) in a 15cm (length) x 1 / 4” (ID) stainless steel tube. The column was filled and conditioned using a slurry method, following references (Cong, R.; Parrott, A.; Hollis, C.; Cheatham, M. WO2017040127A1). The final pressure of the TCB slurry filling was 150 bar.

[0178] Column temperature calibration was performed using a mixture of a reference material, linear homopolymer polyethylene (with zero comonomer content, melt index (I2) of 1.0, polydispersity Mw / Mn of approximately 2.6 by conventional gel permeation chromatography, 1.0 mg / ml) and ODCB containing eicosane (2 mg / ml). The iCCD temperature calibration consisted of four steps: (1) calculating the delay volume, which was defined as the measured peak elution temperature of eicosane minus the temperature bias between 30.00 °C and the measured peak elution temperature; and (2) subtracting the temperature bias of the elution temperature from the raw iCCD temperature data. It should be noted that the temperature bias is a function of experimental conditions, such as elution temperature, elution flow rate, etc.; (3) Create a linear calibration line by switching the elution temperature in the range of 30.00°C to 140.00°C so that the linear homopolymer polyethylene reference has a peak temperature of 101.0°C and the eicosane has a peak temperature of 30.0°C; (4) For the soluble fraction measured isothermally at 30°C, the elution temperature below 30.0°C is linearly extrapolated by using an elution heating rate of 3°C / min, according to the reference (Cerk and Cong et al., US9,688,795).

[0179] A relationship between comonomer content and iCCD elution temperature was constructed using 12 reference materials (ethylene homopolymers and ethylene-octene random copolymers prepared with unit-point metallocene catalysts, with ethylene equivalent weight-average molecular weights ranging from 35,000 to 128,000). All these reference materials were analyzed in the same manner as previously specified at 4 mg / mL. The reported elution peak temperatures were linearly fitted to the linear equation y = -6.3515x + 101.00, where y represents the iCCD elution temperature, x represents octene mol%, and R0... 2 It is 0.978.

[0180] By assuming a shape factor of 1 and all virial coefficients equal to zero, the molecular weight of the polymer and polymer fractions were determined directly from the LS detector (90-degree angle) and the concentration detector (IR-5) according to the Rayleigh-Gans-Debys approximation (Striegel and Yau, Modern Size Exclusion Liquid Chromatogram, pp. 242 and 263). An integration window was set to integrate all chromatograms over an elution temperature range of 23.0 °C to 120 °C (temperature calibration specified above).

[0181] Calculating molecular weight (Mw) from an iCCD involves the following four steps:

[0182] (1) Measurement of the bias between detectors. The bias is defined as the geometric volume bias between the LS detector and the concentration detector. It is calculated as the difference in elution volume (mL) of the polymer peak between the concentration detector and the LS chromatogram. This is converted to temperature bias using elution heat rate and elution flow rate. Linear high-density polyethylene (comonomer content of zero, melt index (I2) of 1.0) was used, and polydispersity M2 was obtained by conventional gel permeation chromatography. w / M n (Approximately 2.6). The same experimental conditions as the standard iCCD method described above were used, except for the following parameters: crystallization from 140°C to 137°C at 10°C / min, followed by 1 minute of thermal equilibration at 137°C as the elution time for the soluble fraction, and elution of the soluble fraction (SF) from 137°C to 142°C at 3°C / min. The flow rate during crystallization was 0.0 mL / min. The flow rate during elution was 0.80 mL / min. The sample concentration was 1.0 mg / mL.

[0183] (2) Before integration, each LS data point in the LS chromatogram is shifted to correct for detector bias.

[0184] (3) The baseline minus the LS and concentration chromatograms over the entire elution temperature range of step (1) is integrated. The MW detector constant is calculated using known MW HDPE samples in the range of 100,000 to 140,000 Mw and the area ratio of the integrated LS and concentration signals.

[0185] (4) The Mw of the polymer was calculated by using the ratio of the integrated light scattering detector (90-degree angle) to the concentration detector and the MW detector constant.

[0186] The half-peak width is calculated as the temperature difference between the front and back of the maximum peak height at half the peak height. The front temperature at half the maximum peak height is searched forward from 35.0℃, while the back temperature at half the maximum peak height is searched backward from 119.0℃.

[0187] Zero shear viscosity ratio (ZSVR)

[0188] ZSVR is defined as the ratio of the zero-shear viscosity (ZSV) of branched polyethylene to that of linear polyethylene at equivalent weight-average molecular weight (Mw-gpc), according to equations 8 and 9 below:

[0189]

[0190]

[0191] ZSV values ​​were obtained by creep testing at 190°C using the method described above. Mw-gpc values ​​were determined by the conventional GPC method (Equation 5 in the conventional GPC method description). The correlation between ZSV and Mw-gpc for linear polyethylene was established based on a series of linear polyethylene reference materials. A description of the ZSV-Mw relationship can be found in the following literature: ANTEC Conference: Karjala, Teresa P., Sammler, Robert L., Mangnus, Marc A., Hazlitt, Lonnie G., Johnson, Mark S., Hagen, Charles M. Jr., Huang, Joe WL, Reichek, Kenneth N., “Detection of low levels of long-chain branching in polyolefins”, Annual Technical Conference of the Society of Plastics Engineers (2008), Vol. 66, pp. 887-891.

[0192] Example

[0193] Example 1: Preparation of polyethylene compositions 1-3 of the present invention and comparative composition C

[0194] Preparation of polyethylene composition 1 and comparative composition C of the present invention

[0195] The polyethylene composition 1 of the present invention (abbreviated as "PE composition 1 of the present invention") is prepared according to one or more embodiments described in detail, by means of the method described below and using the catalyst and reactor described below. Comparative composition C (abbreviated as "comparative composition C") is prepared by means of the method described below and using the catalyst and reactor described below.

[0196] All feedstocks (monomers and comonomers) and process solvents (narrow-boiling-range, high-purity isoparaffin solvent, Isopar-E) were purified using molecular sieves before being introduced into the reaction environment. Hydrogen was supplied pressurized at a high purity level without further purification. The monomer feed stream to the reactor was pressurized above the reaction pressure using a mechanical compressor. The solvent and comonomer feed streams were pressurized above the reaction pressure using pumps. Each catalyst component was manually diluted in batches with the purified solvent and pressurized above the reaction pressure. All reaction feed streams were measured using mass flow meters and independently controlled by a computer-automated valve control system.

[0197] The two reactor systems are used in series, such as Figure 2The continuous solution polymerization reactor is depicted as a liquid-filled, non-adiabatic isothermal circulating loop reactor simulating a continuous stirred tank reactor (CSTR) with deheating. All fresh solvent, monomer, comonomer, hydrogen, and catalyst components can be independently controlled. The total fresh feed stream (solvent, monomer, comonomer, and hydrogen) to each reactor is temperature-controlled to maintain a single solution phase by passing the feed stream through a heat exchanger. The total fresh feed to each polymerization reactor is injected into the reactor at two locations, with approximately equal reactor volumes between each injection location. The fresh feed is controlled such that each injector receives half the total fresh feed mass flow rate. The catalyst component is injected into the polymerization reactor through an injection insert. The catalyst feed is computer-controlled to maintain the monomer conversion of each reactor at a specified target. The co-catalyst component is fed into the main catalyst component based on a calculated specified molar ratio. Immediately following each reactor feed injection location, the feed stream is mixed with the contents of the circulating polymerization reactor using a static mixing element. The contents of each reactor are continuously circulated through a heat exchanger, which removes most of the heat of reaction, and the temperature on the coolant side is responsible for maintaining the isothermal reaction environment at the specified temperature. Circulation around each reactor loop is provided by a pump.

[0198] The effluent from the first polymerization reactor (containing solvent, monomer, comonomer, hydrogen, catalyst components and polymer) leaves the first reactor loop and is added to the second reactor loop.

[0199] The effluent from the second reactor enters a region where the polymer is deactivated by adding a suitable reagent (water) and reacting with it. At the same reactor outlet location, additional additives are added to stabilize the polymer (typical antioxidants suitable for stability during extrusion and film manufacturing processes, such as octadecyl 3,5-di-tert-butyl-4-hydroxyhydrocinnamate, tetra(methylene(3,5-di-tert-butyl-4-hydroxyhydrocinnamate))methane, and tris(2,4-di-tert-butyl-phenyl)phosphite).

[0200] After catalyst deactivation and the addition of additives, the effluent from the second reactor enters a volatilization system, where polymers are removed from the non-polymer stream. The separated polymer melt is granulated and collected. The non-polymer stream is separated by various devices that handle most of the ethylene removed from the system. Most of the solvent and unreacted comonomers are recycled back to the reactor after passing through a purification system. Small amounts of solvent and comonomers are removed from the process.

[0201] The reactor feed data stream corresponds to the values ​​used in Table 1. Presenting the data makes it easier to account for the complexity of the solvent recycling system, and the reaction system can be treated more simply as a once-through flow diagram. Table 2 shows the catalysts mentioned in Table 1.

[0202] Preparation of polyethylene compositions 2-3 of the present invention

[0203] The polyethylene compositions 2-3 of the present invention (abbreviated as "PE compositions of the present invention #") are described according to one or more embodiments described in detail, and are prepared by the methods described below and using the catalysts and reactors described below.

[0204] All feedstocks (monomers and comonomers) and process solvents (narrow-boiling-range, high-purity isoparaffin solvent, Isopar-E) were purified using molecular sieves before being introduced into the reaction environment. Hydrogen was supplied pressurized at a high purity level without further purification. The monomer feed stream to the reactor was pressurized to above the reaction pressure via a mechanical compressor. The solvent and comonomer feed streams were pressurized to above the reaction pressure via pumps. Individual catalyst components were manually diluted in batches with purified solvent and pressurized to above the reaction pressure. All reaction feed streams were measured by mass flow meters and independently controlled by a computer-automated valve control system.

[0205] The two reactor systems are used in series, such as Figure 2 The first reactor is a continuous solution polymerization reactor consisting of a liquid-filled, non-adiabatic isothermal circulating loop reactor simulating a deheated continuous stirred tank reactor (CSTR). All fresh solvent, monomer, comonomer, hydrogen, and catalyst components can be independently controlled. The total fresh feed stream (solvent, monomer, comonomer, and hydrogen) to the first reactor is temperature-controlled to maintain a single solution phase by passing the feed stream through a heat exchanger. The total fresh feed to the first polymerization reactor is injected into the reactor at two locations, with the reactor volume approximately equal between each injection point. The fresh feed is controlled by receiving half the total fresh feed mass flow rate at each injector. The catalyst components are injected separately from the fresh feed into the polymerization reactor. The main catalyst component feed is computer-controlled to maintain the reactor monomer conversion at a specified value. The co-catalyst component is fed based on a molar ratio to the main catalyst component. Immediately following each first reactor feed injection point, the feed stream is mixed with the contents of the circulating polymerization reactor using static mixing elements. The contents of the first reactor are continuously circulated through a heat exchanger, which is responsible for removing a large amount of the heat of reaction, and the temperature on the coolant side is responsible for maintaining the isothermal reaction environment at a specified temperature. Circulation around the first reactor loop is provided by a pump.

[0206] The second reactor is a continuous solution polymerization reactor consisting of a fully liquid, adiabatic, continuously stirred tank reactor (CSTR). All fresh solvent, monomer, comonomer, hydrogen, and catalyst components can be independently controlled in the feed. The total fresh feed stream (solvent, monomer, comonomer, and hydrogen) to the second reactor is temperature-controlled to maintain a single solution phase by passing the feed stream through a heat exchanger. All fresh feed to the second polymerization reactor is injected into the reactor from a single location. The catalyst component is injected into the second polymerization reactor separately from the fresh feed. The main catalyst component feed is computer-controlled to maintain the reactor monomer conversion at a specified value. The cocatalyst component is fed based on its molar ratio with the main catalyst component. Mixing in the second reactor is provided by a stirrer. The effluent from the first polymerization reactor (containing solvent, monomer, comonomer, hydrogen, catalyst component, and polymer) exits the first reactor loop and is added to the second reactor separately from the fresh feed and the catalyst feed component.

[0207] The effluent from the second reactor enters a region where the polymer is deactivated by adding a suitable reagent (water) and reacting with it. At the same reactor outlet location, additional additives are added to stabilize the polymer (typical antioxidants suitable for stability during extrusion and film manufacturing processes, such as octadecyl 3,5-di-tert-butyl-4-hydroxyhydrocinnamate, tetra(methylene(3,5-di-tert-butyl-4-hydroxyhydrocinnamate))methane, and tris(2,4-di-tert-butyl-phenyl)phosphite).

[0208] After catalyst deactivation and the addition of additives, the reactor effluent enters the volatilization system, where polymers are removed from the non-polymer stream. The separated polymer melt is granulated and collected. The non-polymer stream is separated by various devices that handle most of the ethylene removed from the system. Most of the solvent and unreacted comonomers are recycled back to the reactor after passing through a purification system. Small amounts of solvent and comonomers are removed from the process.

[0209] The reactor feed data stream corresponds to the values ​​used in Table 1. Presenting the data makes it easier to account for the complexity of the solvent recycling system, and the reaction system can be treated more simply as a once-through flow diagram. Table 2 shows the catalysts mentioned in Table 1.

[0210] Table 1

[0211]

[0212]

[0213] Table 2

[0214]

[0215]

[0216] Example 2: Comparative composition AC

[0217] Table 3 identifies the commercially available polyethylene compositions for comparative polyethylene compositions (“comparative PE compositions”) AB. Comparative PE composition C is as described in Example 1 above.

[0218] Table 3

[0219] Comparison of PE compositions Business Name (Manufacturing Company) A <![CDATA[ELITE TM AT 6410 (Dow Chemical Company) B <![CDATA[ELITE TM AT 6501 (Dow Chemical Company)

[0220] Example 3: Comparison of the polyethylene compositions 1-3 of the present invention in Example 1 and the polyethylene composition AC in Example 2 Analysis

[0221] Table 4 reports the density and melt flow index (I2) of polyethylene compositions 1-3 and comparative polyethylene composition AC of the present invention. Furthermore, for some compositions, molecular weights were measured using gel permeation chromatography (GPC), and molecularly weighted comonomer distribution index (MWCDI) values ​​were determined, each using the techniques described in the above-described test methods section. These values ​​are shown in Table 4.

[0222] Table 4

[0223]

[0224] The polyethylene compositions 1-3 of the present invention from Example 1 and the comparative polyethylene composition AC from Example 2 were analyzed by iCCD. Table 5 provides data from iCCD tests of all samples (polyethylene compositions 1-3 of the present invention from Example 1 and comparative polyethylene composition AC). Specifically, Table 5 includes the analysis of iCCD data for three polyethylene fractions: 40°C to 75°C, 75°C to 85°C, and 85°C to 110°C.

[0225] Table 5

[0226] Sample ID 40℃-75℃ 75℃-85℃ 85℃-110℃ Comparison of PE composition A 31.3％ 66.2％ 1.97％ Comparison of PE composition B 48.2％ 33.8％ 17.4％ Comparison of PE composition C 55.8％ 37.9％ 5.1％ PE composition 1 of the present invention 51.2％ 21％ 27％ PE composition 2 of the present invention 55.7％ 7.8％ 34％ PE composition 3 of the present invention 61.6％ 11.9％ 25％

[0227] Furthermore, the weight-average molecular weight (M) of each polyethylene fraction of the polyethylene compositions 1-3 and the comparative composition AC of the present invention is as follows: w The data were calculated by iCCD, as described in the Test Methods section. The data are shown in Table 6. Table 6 also shows the M of the first polyethylene fraction ([A], 40℃-75℃). w M with the second polyethylene grade ([B], 75℃-85℃) wThe ratio (“[A] / [B]”) and the M of the second polyethylene fraction ([B], 75℃-85℃) w M with the third polyethylene grade ([C], 85℃-110℃) w The ratio (“[B] / [C]”).

[0228] Table 6

[0229]

[0230] Example 4: Analysis of heat-sealing initiation temperature and heat-bonding initiation temperature

[0231] In Example 4, the heat-sealing initiation temperature, heat-tack initiation temperature, and peak heat tack of the film containing the polyethylene composition described herein were analyzed.

[0232] To analyze these properties, multilayer films were co-extruded on an Alpine 7-layer blown film production line. This line is equipped with seven 50mm single-screw extruders (30L / D each) and 250mm dies. Three-layer (top layer, core, and sealant) films with a total thickness of 50 micrometers were prepared. The top layer / core / sealant layer thickness ratio was set to 1 / 3 / 1 (10 micrometers / 30 micrometers / 10 micrometers). The top layer consisted of DOWLEX at a weight ratio of 80 / 20. TM 2045G / DOW TM The composition is based on a blend of LDPE 611A, both of which are available from Dow Chemical Company. The base resin for the core layer contains the same blend as the top layer, but additionally includes 500 ppm of 10090 Slip PE MB (erucamide, available from Ampacet) and 10063 Antiblock PE MB (available from Ampacet), which are added via dry blending. The polyethylene compositions used in the sealant layers vary and are provided in Table 7. 750 ppm of 10090 Slip PE MB and 2500 ppm of 10063 Antiblock PE MB are introduced into the sealant layers via dry blending. The die gap is set at 78.7 mils, the blow-up ratio at 2.5, the melt temperature at 440℉–470℉, the output rate at 350 lb / hr, and the cooling line height at approximately 37 inches. The bubbles in the multilayer film are cut inline and separated into two rolls.

[0233] Table 7

[0234] sample sealant layer Comparison membrane A <![CDATA[ELITE TM AT 6410 (Dow Chemical Company) Comparison membrane B <![CDATA[ELITE TM AT 6501 (Dow Chemical Company) Comparison membrane C Comparison of PE composition C Membrane 1 of the present invention PE composition 1 of the present invention Membrane 2 of the present invention PE composition 2 of the present invention Membrane 3 of the present invention PE composition 3 of the present invention

[0235] Then, using a Nordmeccanica Super Combi 3000 laminator and ADCOTE TM577 / CR 87-124 solvent-based adhesive is used to laminate each of the films 1-3 of the present invention and the comparative film AC onto a 12-micron-thick oriented polyethylene terephthalate (PET) film, wherein ADCOTE TM Components 577 and CR 87-124 were mixed at a weight ratio of 100:7. Before applying the solvent-based binder, the surface side of each of the films 1-3 of the present invention and the comparative film AC was corona-discharged with 1 kW. Using a 150-channel four-roller coating binder with 11.5 bcm, a coating weight of 1.75 lbs / rm was produced by gravure rollers, followed by extrusion at 160℉. The films were cured at 25°C and 40% relative humidity for at least 5-7 days for complete chemical curing, resulting in laminated films 1-3 and the comparative laminated film AC.

[0236] According to ASTM F-1921 (Method B), the thermal tack of each of the laminates 1-3 and the comparative laminate AC was measured using an Enepay commercial testing machine. Prior to testing, the samples were conditioned at 23°C and 50% RH for at least 40 hours according to ASTM D-618 (Procedure A).

[0237] Sheets measuring 8.5 inches x 14 inches were cut from the membrane, with the longest dimension being longitudinal. Strips 1 inch wide and 14 inches long were also cut from the membrane. These samples were tested within a defined temperature range, and the results were reported as the maximum load as a function of temperature. Typical temperature steps were 5°C or 10°C, with 6 replicates at each temperature. Typical parameters used in the tests are as follows:

[0238] Sample width: 25.4 mm (1.0 inch)

[0239] Sealing pressure: 0.275 N / mm 2

[0240] Seal dwell time: 0.5s

[0241] Delay time: 0.18s

[0242] Peeling speed: 200mm / s

[0243] Sealing depth = 0.5 inches

[0244] A thermoviscosity curve was generated by linear interpolation of the average maximum load measured at each temperature. The minimum temperature at which the average maximum load of 4 N is reached (defined as the thermoviscosity onset temperature) was determined from this curve and is recorded in Table 8. The maximum average load (defined as the peak thermoviscosity) determined by the thermoviscosity curve is also shown.

[0245] According to ASTM F-88 (Method A), heat seal measurements of each of the laminates 1-3 and the comparative laminate AC were performed using a commercial tensile testing machine.

[0246] Before cutting, condition the film at 23°C (±2°C) and 50% (±10%) RH for at least 40 hours according to ASTM D-618 (Program A). Then, cut sheets approximately 11 inches long and 8.5 inches wide from the film longitudinally. Heat-seal the sheets longitudinally on a Kopp heat sealer under the following typical conditions and within a defined temperature range:

[0247] Sealing pressure: 0.275 N / mm 2

[0248] Seal dwell time: 0.5s (<1 mil) or 1.0s (>1 mil)

[0249] Sealing depth = 5mm

[0250] Before cutting into one-inch wide strips, conditioned the sealed sheet at 23°C (±2°C) and 50% RH (±10%) for at least 3 hours. Before testing, conditioned the sample at 23°C (±2°C) and 50% RH (±10%) for at least 24 hours after sealing.

[0251] For testing, the strips were loaded into the clamps of a tensile testing machine at an initial spacing of 2 inches at 23°C (±2°C) and 50% RH (±10%), and stretched at a clamp spacing rate of 10 inches / minute. The strips were tested without support. Five repeated tests were performed for each sealing temperature.

[0252] The maximum load measured during the peeling process was determined at multiple sealing temperatures, and the heat-sealing curve was obtained by linear interpolation of the average maximum load measured at each temperature. The temperature at which the average maximum load of 2 lb was reached (defined as the heat-sealing initiation temperature) was determined from this curve, as shown subsequently in Table 8.

[0253] Table 8

[0254]

[0255]

[0256] It is known that the heat-sealing initiation temperature and the heat-tack initiation temperature are affected by the total density of the polyethylene composition. Therefore, the appropriate comparisons in Table 8 are: (1) laminated films 1-2 with comparative laminated films 1-2, and (2) laminated film 3 with comparative laminated film C. As shown in Table 8, in each comparable group, the polyethylene compositions using some embodiments of the present invention exhibit the lowest heat-tack initiation temperature and the lowest heat-sealing initiation temperature compared to the comparative PE compositions.

Claims

1. A polyethylene composition suitable for packaging applications, the polyethylene composition comprising: (a) a first polyethylene fraction having a single peak in an elution profile obtained by a modified comonomer composition distribution iCCD analysis method in the temperature range from 40°C to 75°C, wherein a first polyethylene fraction area is the area under the single peak of the first polyethylene fraction between 40°C and 75°C in the elution profile, and wherein the first polyethylene fraction area represents from 45% to 65% of the total area of the elution profile; and (b) a second polyethylene fraction in the temperature range from 85°C to 110°C in the elution profile obtained by the iCCD analysis method, and wherein a second polyethylene fraction area is the area under at least one peak of the second polyethylene fraction between 85°C and 110°C in the elution profile, and wherein the second polyethylene fraction area represents from 15% to 35% of the total area of the elution profile; wherein the polyethylene composition has a density of 0.905 g / cm 3 to 0.918 g / cm 3 and wherein the polyethylene composition has a melt index I2 of 0.7 g / 10 min to 3.5 g / 10 min, and wherein the ratio of the melt indices I 10 / I2 fulfils the following relationship: I 10 / I2 < 7.0 - 1.2 log(I2), wherein the melt index I2 is measured according to ASTM D-1238 at 190 °C and under a load of 2.16 kg, and the melt index I 10 is measured according to ASTM D-1238 at 190 °C and under a load of 10 kg, and wherein the polyethylene composition has a melt strength of at least 5 cN. wherein the iCCD analysis method is performed with a Crystallization Elution Fractionation instrument CEF equipped with an IR-5 detector and a two-angle light scattering detector, the temperature profile being: crystallization from 105°C to 30°C at 3°C / minute, thermal equilibration at 30°C for 2 minutes, and elution from 30°C to 140°C at 3°C / minute.

2. The polyethylene composition according to claim 1, wherein, The ratio of the weight average molecular weight of the first polyethylene fraction in the temperature range from 40°C to 75°C in the elution profile obtained by the iCCD analysis method to the weight average molecular weight of a third polyethylene fraction in the temperature range from 75°C to 85°C in the elution profile obtained by the iCCD analysis method is from 0.90 to 1.

6.

3. The polyethylene composition of claim 2, wherein the ratio of the weight average molecular weight of the third polyethylene fraction to the weight average molecular weight of the second polyethylene fraction in the temperature range from 85°C to 110°C in the elution profile obtained by the iCCD analysis method is from 0.50 to 1.

50.

4. The polyethylene composition of any one of claims 1 to 3, wherein the polyethylene composition has a zero shear viscosity ratio of less than 2.0, wherein the zero shear viscosity test is performed on an AR-G2 stress controlled rheometer using 25 mm diameter parallel plates at 190°C.

5. The polyethylene composition of any one of claims 1 to 3, wherein the second polyethylene fraction has at least one peak in the temperature range from 85°C to 110°C.

6. The polyethylene composition of any one of claims 1 to 3, wherein the polyethylene composition has a molecular weight distribution expressed as the ratio of weight average molecular weight to number average molecular weight Mw / Mn in the range from 2.0 to 3.

5.

7. The polyethylene composition of any one of claims 1 to 3, wherein the polyethylene composition has a molecular weighted comonomer distribution index MWCDI of less than 1.

0.

8. A film comprising the polyethylene composition of any one of claims 1 to 7.

9. A multilayer film comprising a sealant layer, wherein the sealant layer comprises the polyethylene composition of any one of claims 1 to 7.

10. An article comprising the polyethylene composition of any one of claims 1 to 7.

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