Polyethylene copolymer for a film layer

Abstract

The present invention relates to a metallocene catalysed multimodal polyethylene copolymer (P), the use of the multimodal copolymer of ethylene (P) in film applications and a film comprising the polymer composition of the invention.

Description

Technical Field

[0001] This invention relates to metallocene-catalyzed multimodal polyethylene copolymers (P), the use of multimodal polyethylene copolymers (P) in membrane applications, and membranes comprising the polymer compositions of this invention. Background Technology

[0002] Due to its excellent cost-effectiveness, existing mLLDPE (metallocene-catalyzed linear low-density polyethylene) is widely used in various aspects of daily life, such as packaging. One significant drawback is its narrow molecular weight distribution, resulting in low shear thinning, which leads to membrane conversion problems, such as limiting throughput.

[0003] Borealis' WO 2021009189, WO 2021009190 and WO 2021009191 disclose methods for preparing multi-peak PE polymers in two loop reactors and one gas-phase reactor.

[0004] The total density of the polymer produced in the examples is 938 or 939 kg / m³. 3 The MFR2 (190°C, 2.16 kg, ISO 1133) of the polymer component produced in the first loop reactor was 22 g / 10 min. No mention was made of membrane properties such as tensile modulus (TM) or dart impact strength (DDI).

[0005] WO 2021009192 also discloses such a method. The polymer produced in the examples has an even higher density, at 951 kg / m³. 3 The MFR2 (190°C, 2.16 kg, ISO 1133) of the polymer component produced in the first loop was 32 g / 10 min. No mention was made of membrane properties such as tensile modulus (TM) or dart impact strength (DDI).

[0006] WO2021013552, Reference Example RE3 discloses a polymer comprising an ethylene-1-butene polymer component and an ethylene-1-hexene polymer component, which is produced using bis(1-methyl-3-n-butylcyclopentadienyl)zirconium dichloride (IV) as a metallocene complex in a loop reactor and a gas-phase reactor. The membrane produced using this polymer has a dart impact strength of only 345 g.

[0007] WO2021191018 discloses a method for preparing multimodal PE polymers using bis(1-methyl-3-n-butylcyclopentadienyl)zirconium dichloride (IV) as a metallocene complex in two loop reactors and one gas-phase reactor. The polymer produced in the gas-phase reactor according to IE1 has an MFR2 of 1.65 g / 10 min. Membranes made from this polymer exhibit a relatively high haze of 42.2%.

[0008] WO2016083208 again discloses a polymer comprising ethylene-1-butene and ethylene-1-hexene polymer components, which is produced using bis(1-methyl-3-n-butylcyclopentadienyl)zirconium dichloride (IV) as a metallocene complex in a loop reactor and a gas-phase reactor. No mention is made of membrane properties, such as dart impact strength (DDI).

[0009] US2014194277 discloses blends of two different separately produced (each in only one reactor) polyethylene copolymers (A) and (B). No mention is made of membrane properties such as dart impact strength (DDI).

[0010] Despite significant development efforts in this field, there remains a need to find multimodal PE polymers with varying performance balances to provide tailored solutions that meet the growing demands of end-application manufacturers, such as reducing production costs while maintaining or even improving the performance of the final product. Customized polymer solutions are also required to meet the evolving equipment technology requirements of end-application sectors.

[0011] A common problem with cutting performance is that an improvement in one property often leads to a deterioration in another; for example, increasing stiffness usually results in a decrease in toughness.

[0012] Therefore, there is a need in the art for a material that provides a good balance of mechanical properties, particularly dart (impact strength) and tensile modulus; that is, high stiffness and high toughness.

[0013] In other words, a material is needed that provides a favorable combination of tensile modulus and dart drop for films prepared from it.

[0014] Furthermore, such membranes should exhibit well-balanced and continuously improving overall performance.

[0015] Such improvements in the overall performance of blown film can be represented by optomechanical capability (OMA), which is the ratio of mechanical properties (especially dart impact strength (DDI) and tensile properties (MD)) to optical properties (i.e., haze).

[0016] It has now been found that metallocene-catalyzed multimodal polyethylene copolymers (P) with specific polymer designs, prepared using specific metallocene catalysts, possess such desired improved properties.

[0017] Films made from such metallocene-catalyzed multimodal polyethylene copolymers (P) also have an improved balance of performance, particularly in terms of higher stiffness (i.e., tensile modulus) and higher impact strength (i.e., drop weight impact, DDI), as well as good optical properties. Summary of the Invention

[0018] Therefore, the present invention relates to a metallocene-catalyzed multimodal polyethylene copolymer (P) having the following composition:

[0019] (i) 35.0 to 50.0 wt% of ethylene-1-butene polymer component (A), and

[0020] (ii) 50.0 to 65.0 wt% of ethylene-1-hexene polymer component (B),

[0021] The ethylene-1-butene polymer component (A) has

[0022] Between 920 and 950 kg / m 3 Density within a certain range

[0023] MFR2 in the range of 2.0 to 20.0 g / 10 min (190 °C, 2.16 kg, ISO 1133).

[0024] Based on the ethylene-1-butene polymer component (A), the 1-butene content ranges from 0.1 to 2.0 mol%.

[0025] The ethylene-1-butene polymer component (A) is composed of an ethylene-1-butene polymer moiety (A-1) and an ethylene-1-butene polymer moiety (A-2).

[0026] The ethylene polymer portion (A-1) has a strength of 920 to 960 kg / m³. 3 The density is within the range of 1.0 to 15.0 g / 10 min, and the MFR2 (190°C, 2.16 kg, ISO 1133) is within the range of 1.0 to 15.0 g / 10 min.

[0027] The ethylene polymer portion (A-2) has a concentration of 925 to 950 kg / m³. 3 The density is within the range of 1.0 to 15.0 g / 10 min and the MFR2 is within the range of 1.0 to 15.0 g / 10 min (190°C, 2.16 kg, ISO 1133).

[0028] The ethylene polymer component (B) has

[0029] Between 890 and 920 kg / m 3 Density within a certain range

[0030] MFR2 in the range of 0.1 to 2.0 g / 10 min (190 °C, 2.16 kg, ISO 1133).

[0031] Based on ethylene-1-hexene polymer compound (B), the 1-hexene content is in the range of 2.5 to 10.0 mol%.

[0032] Among them, multimodal polyethylene copolymer (P) has

[0033] Between 915 and 925 kg / m 3 Density within a certain range

[0034] MFR2 in the range of 1.0 to 3.0 g / 10 min (190 °C, 2.16 kg, ISO 1133).

[0035] The molecular weight distribution (Mw / Mn) in the range of at least 4.6 to high 7.0 was determined by GPC.

[0036] The ratio of the molecular weight (Mw) of the low-crystallinity fraction (LCF) to the molecular weight (Mw) of the high-crystallinity fraction (HCF) in the range of 1.8 to 4.0 (Mw(Tp(LCF) / Mw(Tp(HCF))), which was determined as described in the experimental section, and

[0037] The full width at half maximum (FWHM) of the low crystallinity fraction (LCF) in a TREF curve with LogM > 5.2 in the range of 5.0 to 20.0, as determined in the experimental section.

[0038] Surprisingly, the multimodal polyethylene copolymer (P) of the present invention provides the film with improved mechanical properties, such as high dart strength (DDI), as well as good tensile modulus.

[0039] Therefore, the present invention further relates to a membrane comprising at least one layer comprising a metallocene-catalyzed multimodal polyethylene copolymer (P).

[0040] In another embodiment of the invention, according to formula (I):

[0041]

[0042] The optical mechanical properties (OMA) of the film, measured on a 40 µm test blown film, are at least 7800 [MPa*g / %] to up to 15000 [MPa*g / %], preferably in the range of 8000 [MPa*g / %] to up to 12000 [MPa*g / %], more preferably in the range of 8200 [MPa*g / %] to up to 10000 [MPa*g / %], wherein the longitudinal tensile modulus is measured on a 40 µm test blown film at 23°C according to ISO 527-3, the DDI is the dart impact strength measured on a 40 µm test blown film according to ASTM D1709, Method A, and the haze is measured on a 40 µm test blown film according to ASTM D1003. Attached Figure Description

[0043] Figure 1 This is a graph showing the content of 1-hexene relative to C6 isolated in the embodiments and comparative examples of the present invention.

[0044] Figure 2 The a-TREF (HMWF) and a-TREF curves for CE2 are shown. Detailed Implementation

[0045] definition

[0046] When the term "comprising / including" is used in this specification, it does not exclude other unspecified elements of primary or secondary functional importance. For the purposes of this invention, the term "consisting of..." is considered a preferred embodiment of the term "comprising / including". If a group is defined below as including at least a certain number of embodiments, this should also be understood as a disclosed group, which preferably consists only of these embodiments.

[0047] Whenever the terms “including” or “having” are used, these terms mean equivalent to “include / comprise” as defined above.

[0048] When referring to a singular noun, use the indefinite or definite article, such as "a", "an", or "the / that", unless otherwise specified, this includes the plural form of the noun.

[0049] In this invention, a metallocene-catalyzed multimodal polyethylene copolymer is defined as a multimodal polyethylene copolymer (P), which is produced in the presence of a metallocene catalyst.

[0050] In the context of multimodal polyethylene copolymers (P), the term "multimodal" herein refers to multimodality in relation to the melt flow rate (MFR) of the ethylene polymer components (A) and (B), i.e., the ethylene polymer components (A) and (B) have different MFR values. As described below, multimodal polyethylene copolymers (P) may further possess multimodality in relation to one or more other properties between the ethylene polymer components (A) and (B).

[0051] The multimodal polyethylene copolymer (P) of the present invention as defined above and below is also referred to herein as "multimodal PE" or "multimodal copolymer (P)".

[0052] The following preferred embodiments, properties, and subgroups of multimodal PE and its ethylene polymer components (A) and (B), and its ethylene polymer portions (A-1) and (A-2), as well as the membranes of the present invention including their preferred ranges, are independently generalizable such that they can be used in any order or combination to further define the preferred embodiments of the multimodal PE and articles of the present invention.

[0053] Multimodal PE as well as ethylene polymer components (A) and (B) and ethylene polymer fractions (A-1) and (A-2)

[0054] The multimodal polyethylene copolymer (P) produced by metallocene is referred to herein as "multimodal" because the ethylene-1-butene polymer component (A), comprising ethylene polymer portions (A-1) and (A-2), and the ethylene-1-hexene polymer component (B) have been produced under different polymerization conditions, resulting in different melt flow rates (MFRs, e.g., MFR2). That is, multimodal PE is multimodal at least with respect to the difference in MFR between the ethylene polymer components (A) and (B).

[0055] Metallocene-produced multimodal polyethylene copolymers (P) consist of the following components:

[0056] (i) 35.0 to 50.0 wt% of ethylene-1-butene polymer component (A), and

[0057] (ii) 50.0 to 65.0 wt% of ethylene-1-hexene polymer component (B).

[0058] The sum of (A) and (B) is 100.0 wt%.

[0059] The ethylene-1-butene polymer component (A) is composed of ethylene polymer parts (A-1) and (A-2), wherein the MFR2 of the ethylene polymer parts (A-1) and (A-2) may be different from each other or may be the same.

[0060] The MFR2 (190°C, 2.16 kg, ISO 1133) of the ethylene polymer fraction (A-1) is in the range of 1.0 to 15.0 g / 10 min, preferably 1.5 to 14.0 g / 10 min, more preferably 2.0 to 12.0 g / 10 min, even more preferably 2.5 to 12.0 g / min, and most preferably 3.0 to 10.0 g / 10 min.

[0061] The MFR2 (190°C, 2.16 kg, ISO 1133) of the ethylene polymer fraction (A-2) is in the range of 1.0 to 15.0 g / 10 min, preferably 1.5 to 14.0 g / 10 min, more preferably 2.0 to 12.0 g / 10 min, even more preferably 2.5 to 12.0 g / min, and most preferably 3.0 to 10.0 g / 10 min.

[0062] The MFR2 of ethylene polymer components (A) and (B) are different from each other.

[0063] The MFR2 (190°C, 2.16 kg, ISO 1133) of the ethylene polymer component (A) is in the range of 2.0 to 20 g / 10 min, preferably 2.5 to 16 g / 10 min, more preferably 3.0 to 12.0 g / 10 min, and even more preferably 3.5 to 10 g / 10 min.

[0064] The MFR2 (190°C, 2.16 kg, ISO 1133) of the ethylene polymer component (B) is in the range of 0.1 to 2.0 g / 10 min, preferably 0.2 to 1.6 g / 10 min, more preferably 0.3 to 1.2 g / 10 min, and even more preferably 0.3 to 1.0 g / 10 min.

[0065] The MFR2 (190°C, 2.16 kg, ISO 1133) of the multimodal copolymer (P) is in the range of 1.0 to 3.0 g / 10 min, preferably 1.0 to 2.5 g / 10 min, more preferably 1.0 to 2.0 g / 10 min.

[0066] Of course, in addition to the multimodality of the MFR2 (i.e., the difference between them) of the ethylene polymer components (A) and (B), the multimodal PE of the present invention can also be multimodal, for example, with respect to one or both of two other properties:

[0067] Multimodality in terms of the differences between the following:

[0068] - The content of comonomers present in ethylene polymer components (A) and (B); and / or

[0069] - Densities of ethylene polymer components (A) and (B).

[0070] Preferably, the multimodal polymer (P) is further multimodal in terms of the difference in MFR between the ethylene polymer components (A) and (B).

[0071] The polymer parts (A-1) and (A-2) have the same type of comonomer, so both parts have 1-butene as a comonomer.

[0072] The comonomer content of components (A) and (B) can be measured, or, in a preferred case, one component is first produced, and then another component is produced in a so-called multi-stage process in the presence of the first-produced component. The comonomer content of the first-produced component (e.g., component (A)) can then be measured, and the comonomer content of the other component (e.g., component (B)) can be calculated according to the following formula:

[0073] Comonomer content in component B (mol%) = (Comonomer content in the final product (mol%) - (Weight fraction of component A * Comonomer content in component A (mol%)) / (Weight fraction of component B)

[0074] Based on the multimodal polymer (P), the total amount of 1-butene is preferably in the range of 0.1 to 1.0 mol%, more preferably 0.2 to 0.8 mol%, and even more preferably 0.2 to 0.6 mol%.

[0075] Based on the multimodal polymer (P), the total amount of 1-hexene is preferably in the range of 1.5 to 8.0 mol%, more preferably 2.0 to 6.0 mol%, and even more preferably 2.2 to 4.0 mol%.

[0076] Based on the ethylene-1-butene polymer component (A), the total amount (mol%) of 1-butene present in the ethylene-1-butene polymer component (A) is 0.1 to 2.0 mol%, preferably 0.2 to 1.6 mol%, more preferably 0.3 to 1.2 mol%, and even more preferably 0.4 to 1.0 mol.

[0077] Based on the ethylene-1-hexene polymer component (B), the total amount (mol%) of 1-hexene present in the ethylene-1-hexene polymer component (B) is 2.5 to 10.0 mol%, preferably 3.0 to 8.0 mol%, more preferably 3.5 to 6.0 mol%.

[0078] Even more preferably, the multimodal polymer (P) of the present invention is further multimodal in terms of the density difference between the ethylene polymer component (A) and the ethylene polymer component (B). Preferably, the density of the ethylene polymer component (A) is different from, and preferably higher than, the density of the ethylene polymer component (B).

[0079] The density of the ethylene polymer component (A) is between 920 and 950 kg / m³. 3 Preferred weight is 925 to 945 kg / m³. 3 More preferably 930 to 942 kg / m 3 Within the range, and / or the density of the ethylene polymer component (B) is between 890 and 920 kg / m³. 3 Preferred weight is 900 to 912 kg / m³. 3 More preferably 900 to 920 kg / m 3 Within the range.

[0080] The density of the polymer portion (A-1) is between 920 and 960 kg / m³. 3 Preferably 925 to 955 kg / m 3 More preferably 930 to 950 kg / m 3 The optimal value is 935 to 945 kg / m³. 3 Within the range.

[0081] The density of the polymer portion (A-2) is between 925 and 950 kg / m³. 3 Preferably 930 to 940 kg / m 3 Within the range.

[0082] The densities of polymer components (A-1) and (A-2) may be the same or different from each other.

[0083] Metallocene-catalyzed multimodal copolymers (P) are preferably linear low-density polyethylene (LLDPE), which has a well-known meaning.

[0084] The density of the multimodal copolymer (P) is between 915 and 925 kg / m³. 3 Preferably 916.0 to 922 kg / m 3 More preferably 917.0 to 922.0 kg / m 3 Within the range.

[0085] More preferably, the multimodal copolymer (P) is multimodal at least in terms of the MFR2, comonomer content and density of the ethylene polymer components (A) and (B), i.e., having differences as defined above and below, including any preferred range or embodiment of the polymer composition.

[0086] Furthermore, the molecular weight distribution (Mw / Mn) of the multimodal copolymer (P) as determined by GPC is in the range of at least 4.6 to up to 7.0, preferably in the range of 4.8 to 6.8, and more preferably in the range of 5.0 to 6.5.

[0087] Furthermore, as described in the experimental section, the ratio of the molecular weight (Mw) of the low-crystallinity fraction (LCF) to the molecular weight (Mw) of the high-crystallinity fraction (HCF) of the multimodal copolymer (P) (Mw(Tp(LCF) / Mw(Tp(HCF))) is in the range of 1.4 to 4.0, preferably in the range of 1.8 to 3.5, and more preferably in the range of 2.0 to 3.0.

[0088] The half-peak width of the low crystallinity fraction (LCF) of the multi-peak copolymer (P) in the TREF curve with LogM>5.2, as determined in the experimental section, is in the range of 5.0 to 20.0, preferably 6.0 to 16.0, more preferably 7.0 to 14.0, and even more preferably 8.0 to 12.0.

[0089] Definitions of highly crystalline fraction (HCF) and lowly crystalline fraction (LCF):

[0090] The highly crystalline fraction (HCF) is the amount (in wt%) of the polymer fraction with a crystallization temperature above 90°C, mainly containing homopolymer polyethylene chains or chains with very low branching content.

[0091] Low crystallinity fraction (LCF) refers to the amount (in wt%) of polymer fraction with a crystallization temperature between 30°C and below 90°C.

[0092] Within the scope of this invention, the first and second ethylene polymer portions (A-1 and A-2) of the ethylene polymer component (A) are present in a weight ratio of 4:1 to 1:4, for example 3:1 to 1:3, or 2:1 to 1:2, or 1:1.

[0093] Based on the multimodal copolymer (P), the ethylene polymer component (A) is present in an amount of 35.0 to 50.0 wt%, preferably 36.0 to 48.0 wt%, and even more preferably 38.0 to 45.0 wt%.

[0094] Therefore, based on the multimodal copolymer (P), the ethylene polymer component (B) is present in an amount of 50.0 to 65.0 wt%, preferably 52.0 to 64.0 wt%, more preferably 55.0 to 62.0 wt%.

[0095] Metallocene-catalyzed multimodal copolymers (P) can be produced using a three-stage process, preferably comprising a first slurry reactor (loop reactor 1) connected in series with another slurry reactor (loop reactor 2), such that a first ethylene polymer fraction (A-1) produced in loop reactor 1 is fed into loop reactor 2, where a second ethylene polymer fraction (A-2) is produced in the presence of the first fraction (A-1). Loop reactor 2 is then connected in series with a gas-phase reactor (GPR), such that the first ethylene polymer component (A) exiting the second slurry reactor is fed into the GPR to produce a trimodal polyethylene copolymer. In this case, the reaction conditions in the two slurry reactors are selected such that products with different MFRs and / or densities are produced in the two reactors.

[0096] This method is described in particular in WO 2016 / 198273, WO 2021009189, WO 2021009190, WO 2021009191 and WO 2021009192. Full details on how to prepare suitable metallocene-catalyzed multimodal copolymers (P) can be found in these references.

[0097] The appropriate process is the Borstar PE process or the Borstar PE 3G process.

[0098] Therefore, the metallocene-catalyzed multimodal copolymer (P) according to the invention is preferably produced in a loop-loop-gas phase cascade. A prepolymerization step may precede such a polymerization step. The purpose of prepolymerization is to polymerize a small amount of polymer onto the catalyst at low temperatures and / or low monomer concentrations. Prepolymerization can improve the performance of the catalyst in the slurry and / or alter the properties of the final polymer. This prepolymerization step is preferably carried out in the slurry, and the amount of polymer produced in the optional prepolymerization step is accounted for as the amount (wt%) of the ethylene polymer component (A).

[0099] When a prepolymerization step is present, it is preferable that all of the catalyst components be introduced into the prepolymerization step. However, when the solid catalyst components and cocatalysts can be fed separately, it is possible that only a portion of the cocatalyst is introduced into the prepolymerization stage, while the remainder is introduced into the subsequent polymerization stage. Furthermore, in this case, it is necessary to introduce so much cocatalyst into the prepolymerization stage in order to achieve sufficient polymerization reaction therein.

[0100] It should be understood that, within the scope of this invention, the amount of polymer produced during prepolymerization is between 1 and 5 wt% relative to the final metallocene-catalyzed multimodal copolymer (P). This can be considered as part of the first ethylene polymer component (A).

[0101] catalyst

[0102] The metallocene-catalyzed multimodal copolymer (P) used in the method of this invention is prepared using a metallocene catalyst. The metallocene catalyst comprises a metallocene complex and a co-catalyst. The metallocene compound or complex is also referred to herein as an organometallic compound (C).

[0103] Organometallic compounds (C) contain transition metals (M) of elements in groups 3 to 10 of the periodic table (IUPAC 2007), or of the actinides or lanthanides.

[0104] According to the present invention, the term "organometallic compound (C)" includes any metallocene or nonmetallocene compound of transition metals, which has at least one organic (coordinating) ligand and exhibits catalytic activity alone or in combination with a co-catalyst. Transition metal compounds are well known in the art, and the present invention covers compounds from Groups 3 to 10 of the periodic table (IUPAC 2007), such as Groups 3 to 7, or Groups 3 to 6, such as Groups 4 to 6, as well as compounds of lanthanides or actinides.

[0105] In one embodiment, the organometallic compound (C) has the following formula (II):

[0106] (II)

[0107] Each X is independently a halogen atom, C 1-6 -alkyl, C 1-6 -alkoxy, phenyl, or benzyl;

[0108] Each Het is independently a monocyclic heteroaromatic group containing at least one heteroatom selected from O or S;

[0109] L is -R'2Si-, where each R' is independently a C substituted with an alkoxy group having 1 to 10 carbon atoms. 1-20 - Hydrocarbon group or C 1-10 -alkyl;

[0110] M is Ti, Zr, or Hf;

[0111] Each R 1 Same or different, is C 1-6 -alkyl or C 1-6 -alkoxy group;

[0112] Each n is between 1 and 2;

[0113] Each R 2 Same or different, is C 1-6 -alkyl, C 1-6 -alkoxy or -Si(R)3 group;

[0114] Each R is arbitrarily selected by 1 to 3 Cs. 1-6 -alkyl-substituted C 1-10 -alkyl or phenyl; and

[0115] Each p is between 0 and 1.

[0116] Preferably, the compound of formula (II) has the following structure

[0117] (II´)

[0118] Each X is independently a halogen atom, C 1-6 -alkyl, C 1-6 -alkoxy, phenyl, or benzyl;

[0119] L is Me2Si-;

[0120] Each R 1 Same or different, is C 1-6 -alkyl, such as methyl or tert-butyl;

[0121] Each n is between 1 and 2;

[0122] R 2 It is a -Si(R)3 alkyl group; each p is 1;

[0123] Each R is C 1-6 -alkyl or phenyl.

[0124] The highly preferred formula (II) complex is

[0125]

[0126]

[0127] Most preferably, the complex dimethylsilanediylbis[2-(5-trimethylsilylfuran-2-yl)-4,5-dimethylcyclopentadien-1-yl]zirconium dichloride is used.

[0128] More preferably, the ethylene polymer components (A) and (B) of the multimodal copolymer (P) are prepared using the same metallocene catalyst, i.e., in the presence of the same metallocene catalyst.

[0129] To form the catalyst, a co-catalyst, also known as an activator, is used. Co-catalysts containing Al or B are well known and can be used here. Aluminoxanes (e.g., MAO) or boron-based co-catalysts (e.g., borates) are preferred.

[0130] In contrast to Ziegler-Natta catalysis, polyethylene copolymers prepared using site-specific catalysis exhibit characteristics that distinguish them from Ziegler-Natta materials. Specifically, the comonomer distribution is more uniform. This can be visualized using TREF or Crystaf techniques. Catalyst residues can also indicate the catalyst used. Ziegler-Natta catalysts do not contain, for example, Zr or Group IV (Hf) metals.

[0131] Metallocene-catalyzed multimodal copolymers (P) may contain other polymer components and optional additives and / or fillers. When metallocene-catalyzed multimodal copolymers (P) contain other polymer components, the amount of the other polymer components typically varies between 3.0 and 20.0 wt%, depending on the total amount of the metallocene-catalyzed multimodal copolymer (P) and the other polymer components.

[0132] Optional additives and fillers, and their amounts, are common in membrane applications. Examples of such additives include antioxidants, processing stabilizers, UV stabilizers, pigments, fillers, antistatic additives, antiblocking agents, nucleating agents, acid scavengers, and polymer processing aids (PPAs).

[0133] It should be understood here that any additives and / or fillers may optionally be added to a so-called masterbatch containing the corresponding additives and carrier polymers. In this case, based on the total amount (100 wt%) of the polymer composition, the carrier polymer is not calculated in the polymer component of the metallocene-catalyzed multimodal copolymer (P), but rather in the amount of the corresponding additives.

[0134] The membrane of the present invention

[0135] The membrane of the present invention comprises at least one layer containing a metallocene-catalyzed multimodal copolymer (P). The membrane may be a monolayer membrane containing a metallocene-catalyzed multimodal copolymer (P) or a multilayer membrane wherein at least one layer contains a metallocene-catalyzed multimodal copolymer (P). The terms "monolayer membrane" and "multilayer membrane" have well-known meanings in the art.

[0136] The single-layer or multi-layer membranes of the present invention may consist of the metallocene-catalyzed multimodal copolymer (P) itself, or a blend of the metallocene-catalyzed multimodal copolymer (P) with other polymers. In the case of blends, any other polymer is different from the metallocene-catalyzed multimodal copolymer (P), and is preferably a polyolefin. A portion of the aforementioned additives, such as processing aids, may optionally be added to the metallocene-catalyzed multimodal copolymer (P) during the membrane preparation process.

[0137] Preferably, at least one layer of the present invention comprises at least 50 wt%, more preferably at least 60 wt%, even more preferably at least 70 wt%, and still more preferably at least 80 wt% of the metallocene-catalyzed multimodal copolymer (P) of the present invention. Most preferably, the at least one layer of the membrane of the present invention is composed of a metallocene-catalyzed multimodal copolymer (P).

[0138] Therefore, the membrane of the present invention may comprise a single layer (i.e., a monolayer) or may comprise multiple layers. Multilayer membranes typically and preferably comprise at least three layers.

[0139] The film is preferably produced by any conventional film extrusion process known in the art, including cast film and blown film extrusion. Most preferably, the film is a blown or cast film, especially a blown film. For example, a blown film is produced by extrusion via an annular die and by blowing a tubular film by forming bubbles, which then rupture between rolls after solidification. The film can then be cut, diced, or converted (e.g., folded) as needed. Conventional film production techniques can be used in this regard. If the preferred blown or cast film is a multilayer film, then the layers are typically co-extruded. Those skilled in the art will know the appropriate extrusion conditions.

[0140] The membrane according to the invention can undergo post-processing, such as surface modification, lamination, or orientation processes. Such orientation processes can be uniaxial (MDO) or biaxial orientation, with uniaxial orientation being preferred.

[0141] In another preferred embodiment, the membrane is non-oriented.

[0142] The resulting membrane can have any thickness conventional in the art. The membrane thickness is not critical and depends on the end application. Therefore, the membrane can have a thickness of, for example, 300 μm or less, typically 6 to 200 μm, preferably 10 to 180 μm, such as 20 to 150 μm or 20 to 120 μm. If desired, the polymers of the present invention can achieve thicknesses of less than 100 μm, for example, less than 50 μm. Membranes of the present invention with thicknesses even less than 20 μm can also be produced while maintaining good mechanical properties.

[0143] Furthermore, the present invention relates to the use of the articles of the invention as packaging materials, particularly as packaging materials for food and / or medical products.

[0144] The membrane of the present invention is characterized in that, according to ASTM D1709, method A, the dart impact strength (DDI) on a 40 μm monolayer test blown film is at least 780 g to 1500 g, preferably 800 g to 1200 g, and more preferably 850 g to 1000 g.

[0145] Furthermore, the film according to the invention has good stiffness (tensile modulus measured on a 40 μm monolayer blown film according to ISO 527-3), i.e., >160 MPa (in both directions) and good optical properties, i.e., haze (measured on a 40 μm monolayer blown film according to ASTM D1003-00) less than 25%.

[0146] Therefore, the film containing the metallocene-catalyzed multimodal copolymer (P) can further or additionally have a haze of less than 25%, preferably 5% to 24%, more preferably 10% to 23% (measured on a 40 μm monolayer test blown film according to ASTM D 1003-00), and longitudinal (MD) and transverse (TD) tensile moduli in the range of >180 MPa to 350 MPa, preferably 200 MPa to 300 MPa (measured on a 40 μm monolayer test blown film according to ISO 527-3).

[0147] In another embodiment of the invention, according to formula (I):

[0148]

[0149] The optical mechanical properties (OMA) of the film, measured on a 40 µm blown film, are at least 7800 [MPa*g / %] to up to 15000 [MPa*g / %], preferably in the range of 8000 [MPa*g / %] to up to 12000 [MPa*g / %], more preferably in the range of 8200 [MPa*g / %] to up to 10000 [MPa*g / %], wherein the longitudinal tensile modulus is measured on a 40 µm blown film at 23°C according to ISO 527-3, the DDI is the dart impact strength measured on a 40 µm blown film according to ASTM D1709, Method A, and the haze is measured on a 40 µm blown film according to ASTM D1003.

[0150] In view of the present invention, optomechanical capability (OMA) is understood as the ratio of mechanical (particularly dart impact strength (DDI) and tensile (MD)) properties to optical properties (i.e. haze), wherein the mechanical properties are desired to be as high as possible, while the optical properties in the sense of haze are desired to be as low as possible.

[0151] The present invention will be further described with reference to the following non-limiting embodiments.

[0152] Measurement method:

[0153] Unless otherwise stated in the instructions or experimental section, the following methods are used to determine the performance of polymers (including their parts and components) and / or any sample formulations thereof as described in the text or experimental section.

[0154] melt flow rate

[0155] Melt flow rate (MFR) is determined according to ISO 1133 and expressed in g / 10 min. MFR is an indicator of polymer flowability and therefore also an indicator of polymer processing performance. A higher melt flow rate indicates a lower polymer viscosity. The MFR of polyethylene is determined at 190°C. MFR can be determined under different loads, such as 2.16 kg (MFR2), 5 kg (MFR5), or 21.6 kg (MFR6). 21 ).

[0156] Calculation of MFR2 for component B and part (A-2)

[0157] For component B:

[0158] B = MFR2 of component (A)

[0159] C = MFR2 of component (B)

[0160] A = Final MFR2 (mixture) of multimodal polyethylene copolymer (P)

[0161] X = weight fraction of component (A)

[0162] For part (A-2):

[0163] B = MFR2 of Part 1 (A-1)

[0164] C = MFR2 of Part 2 (A-2)

[0165] A = final MFR2 (mixture) of cyclic polymer (= component (A))

[0166] X = weight fraction of part 1 (A-1)

[0167] density

[0168] The density of the polymer was determined according to ASTM D792, Method B (equilibrium density at 23°C) on compression-molded specimens prepared according to EN ISO 1872-2, in kg / m³.

[0169] Comonomer content:

[0170] Quantitative analysis of microstructure using NMR spectroscopy

[0171] Quantitative nuclear magnetic resonance (NMR) spectroscopy is used to quantify the comonomer content of polymers.

[0172] Using a Bruker Avance III 500 NMR spectrometer, the NMR spectrometer was used to measure the NMR spectrometer at 500.13 and 125.76 MHz.1 H and 13 C performs the operation, recording a quantitative value in the molten state. 13 C{ 1 H NMR spectroscopy. All spectra were performed using H NMR spectroscopy. 13 Recordings were performed using a C-optimized 7 mm magic angle rotation (MAS) probe at 150 °C, with all pneumatic setups using nitrogen. Approximately 200 mg of material was loaded into a 7 mm outer diameter (d) zirconia MAS rotor and rotated at 4 kHz. This setup was chosen primarily for the high sensitivity required for rapid identification and accurate quantification. Standard single-pulse excitation was employed, utilizing a 3 s short-cycle delay NOE with an RS-HEPT decoupling scheme. A total of 1024 (1 k) transients were obtained for each spectrum.

[0173] Quantitative 13 C{ 1 The ¹H NMR spectra were processed, integrated, and the relevant quantitative characteristics were determined by integration. All chemical shifts were performed with the bulk methylene signal (δ+) at 30.00 ppm as an internal reference.

[0174] The amount of ethylene was quantified by integrating the number of methylene (δ+) sites per monomer reporter site at 30.00 ppm:

[0175] E = I δ+ / 2

[0176] The existence of isolated comonomer units is corrected based on the number of existing isolated comonomer units:

[0177] Total E = E + (3*B + 2*H) / 2

[0178] B and H are defined for their respective comonomers. Corrections are made in a similar manner when continuous and discontinuous comonomers are incorporated.

[0179] Observing the characteristic signal corresponding to the incorporation of 1-butene, the comonomer fraction was calculated as the fraction of 1-butene in the polymer relative to all monomers in the polymer:

[0180] fB total = B total / (E total + B total + H total)

[0181] The amount of isolated 1-butene incorporated into the EEBEE sequence was quantified by integrating the B2 site at 39.8 ppm as a percentage of the number of reporter sites per comonomer:

[0182] B = I *B2

[0183] If present, the amount of sequentially incorporated 1-butene in the EEBBEE sequence is quantified by the integral of the ααB2B2 site at 39.4 ppm relative to the number of reporter sites per comonomer:

[0184] BB = 2 * IααB2B2

[0185] The amount of discontinuous 1-butene incorporated into the EEBBEE sequence was quantified by integrating the ββB2B2 site at 24.6 ppm as a percentage of the number of reporter sites per comonomer:

[0186] BEB = 2 * IββB2B2

[0187] Since the *B2 and *βB2B2 sites of the isolated (EEBEE) and discontinuously incorporated (EEBEBEE) 1-butene overlap, the total amount of isolated 1-butene incorporated is corrected for the amount of discontinuous 1-butene present:

[0188] B = I *B2 - 2 * I ββB2B2

[0189] No BBB sequence was observed. The total 1-butene content was calculated based on the sum of isolated, continuous, and discontinuously incorporated 1-butene:

[0190] Total B = B + BB + BEB

[0191] Then calculate the total mole fraction of 1-butene in the polymer:

[0192] fB = B total / (E total + B total + H total)

[0193] Characteristic signals corresponding to 1-hexene incorporation were observed, and the comonomer fraction was calculated as the fraction of 1-hexene in the polymer relative to all monomers in the polymer:

[0194] fH total = H total / (E total + B total + H total)

[0195] The amount of isolated 1-hexene incorporated into the EEHEE sequence was quantified by integrating the number of *B4 sites per comonomer reporter site at 38.3 ppm:

[0196] H = I *B4

[0197] If present, the amount of sequentially incorporated 1-hexene in the EEHHEE sequence is quantified by the integral of the ααB4B4 site at 40.5 ppm relative to the number of reporter sites per comonomer:

[0198] HH = 2 * IααB4B4

[0199] If present, the amount of discontinuously incorporated 1-hexene in the EEHEHEE sequence is quantified by the integral of the ββB4B4 site at 24.7 ppm relative to the number of reporter sites per comonomer:

[0200] HEH = 2 * IββB4B4

[0201] No HHH sequence was observed. The total 1-hexene content was calculated based on the sum of isolated, continuous, and discontinuously incorporated 1-hexene:

[0202] H total = H + HH + HEH

[0203] Then calculate the total mole fraction of 1-hexene in the polymer:

[0204] fH = H total / (E total + B total + H total)

[0205] The molar percentage of comonomer incorporated is calculated from the mole fraction:

[0206] B [mol%] = 100 * fB

[0207] H [mol%] = 100 * fH

[0208] The weight percentage of comonomer incorporated is calculated as a mole fraction:

[0209] B [wt%]= 100 *(fB * 56.11) / ((fB * 56.11)+(fH * 84.16)+((1-(fB+fH))*28.05))

[0210] H [wt%] = 100 * ( fH * 84.16 ) / ( (fB * 56.11) + (fH * 84.16) + ((1-(fB + fH)) * 28.05) )

[0211] References:

[0212] Klimke, K., Parkinson, M., Piel, C., Kaminsky, W., Spiess, H.W.,Wilhelm, M., Macromol. Chem. Phys. 2006;207:382.

[0213] Parkinson, M., Klimke, K., Spiess, H.W., Wilhelm, M., Macromol. Chem.Phys. 2007;208:2128.

[0214] Pollard, M., Klimke, K., Graf, R., Spiess, H.W., Wilhelm, M.,Sperber, O., Piel, C., Kaminsky, W., Macromolecules 2004;37:813.

[0215] Filip, X., Tripon, C., Filip, C., J. Mag. Resn. 2005, 176, 239

[0216] Griffin, J.M., Tripon, C., Samoson, A., Filip, C., and Brown, S.P.,Mag. Res. in Chem. 2007 45, S1, S198

[0217] Castignolles, P., Graf, R., Parkinson, M., Wilhelm, M., Gaborieau,M., Polymer 50 (2009) 2373

[0218] Busico, V., Cipullo, R., Prog. Polym. Sci. 26 (2001) 443

[0219] Busico, V., Cipullo, R., Monaco, G., Vacatello, M., Segre, A.L.,Macromoleucles 30 (1997) 6251

[0220] Zhou, Z., Kuemmerle, R., Qiu, X., Redwine, D., Cong, R., Taha, A., Baugh, D. Winniford, B., J. Mag. Reson. 187 (2007) 225

[0221] Busico, V., Carbonniere, P., Cipullo, R., Pellecchia, R., Severn, J.,Talarico, G., Macromol. Rapid Commun. 2007, 28, 1128

[0222] Resconi, L., Cavallo, L., Fait, A., Piemontesi, F., Chem. Rev. 2000,100, 1253

[0223] Molecular weight, molecular weight distribution, Mn, Mw, MWD:

[0224] The molecular weight averages (Mz, Mw, and Mn), molecular weight distribution (MWD), and their widths described by the polydispersity index (PDI = Mw / Mn, where Mn is the number-average molecular weight and Mw is the weight-average molecular weight) were determined by gel permeation chromatography (GPC) according to ASTM D 6474-12 using the following formula:

[0225] (1)

[0226] (2)

[0227] (3)

[0228] For a constant elution volume interval ΔVi, where Ai and Mi are the chromatographic peak slice area and polyolefin molecular weight (MW) related to the elution volume (Vi), respectively, and N is equal to the number of data points obtained from the chromatogram between integration limits.

[0229] High-temperature GPC instruments equipped with infrared (IR) detectors (PolymerChar (Valencia, Spain) IR4 or IR5) or Agilent Technologies differential refractometers (RI) equipped with three Agilent-plgel Olexis and one Agilent-plgel Olexis Guard columns were used. 1,2,4-trichlorobenzene (TCB) stabilized with 250 mg / L 2,6-di-tert-butyl-4-methylphenol was used as both solvent and mobile phase. The chromatographic system was run at a constant flow rate of 1 mL / min at 160 °C. 209.5 μL of sample solution was injected for each analysis. Data collection was performed using Agilent Cirrus version 3.3 software or PolymerChar GPC-IR control software.

[0230] The column was calibrated using universal calibration with 19 polystyrene (PS) standards ranging from 0.5 kg / mol to 11500 kg / mol with narrow molecular weight distributions (MWDs). The PS standards were dissolved at room temperature for several hours. The conversion of the polystyrene peak molecular weight to the polyolefin molecular weight was performed using the Mark Houwink equation and the following Mark Houwink constant:

[0231] K PS = 19 x 10 -3 mL / g, α PS = 0.655

[0232] K PE = 39 x 10 -3 mL / g, α PE = 0.725

[0233] The calibration data were fitted using a third-order polynomial fitting method.

[0234] All samples were prepared at concentrations ranging from 0.5 to 1 mg / ml and dissolved at 160 °C for 3 hours with continuous slow shaking (PE).

[0235] Mw(Tp(LCF) / Mw(Tp(HCF)) and full width at half maximum (LCF) of TREF curves with LogM>5.2

[0236] The fully automated cross-fractional chromatography (CFC) described by Ortin A., Monrabal B., Sancho-Tello J., Macromol. Symp., 2007, 257, 13-28 determined the chemical composition distribution, molecular weight distribution, and corresponding molecular weight averages (Mn, Mw, and Mv) (polymer crystallinity in solution) at a given elution temperature.

[0237] Cross-fractional chromatography (TREF xSEC) was performed using a CFC instrument (PolymerChar, Valencia, Spain). Concentrations were monitored using a four-band IR5 infrared detector (PolymerChar, Valencia, Spain). Approximately 40 mg of polymer sample was dissolved in 25 ml of TCB in a stainless steel container at 150 °C for 150 min. After complete dissolution, 0.5 ml aliquots were immediately loaded into a TREF column and stabilized at 110 °C for 60 min. The polymer was then cooled to 30 °C at a constant cooling rate of 0.1 °C / min to allow crystallization and precipitation. Discontinuous elution was performed using the following temperature steps: (35, 40, 45, 50, 53, 56, 59, 62, 64, 66, 69, 72, 76, 79, 82, 85, 89, 91, 93, 95, 97, 100, 110, and 120).

[0238] In the two-dimensional GPC analysis, three PL Olexis columns and one Olexis Guard column from Agilent (Church Stretton, UK) were used as the stationary phase. 1,2,4-Trichlorobenzene (TCB, stabilized with 250 mg / L 2,6-di-tert-butyl-4-methylphenol) was used as the eluent at a constant flow rate of 1 mL / min at 150 °C. The column assembly was calibrated using universal calibration (according to ISO 16014-2:2003) with at least 15 polystyrene (PS) standards with narrow MWD ranging from 0.5 kg / mol to 11500 kg / mol. The PS molecular weight was converted to PE molecular weight equivalent using the following Mark Houwink constant.

[0239] K PS = 19 x 10 -3 mL / g, α PS = 0.655

[0240] K PE = 39 x 10 -3 mL / g, α PP = 0.725

[0241] The calibration data were fitted using a third-order polynomial. Data processing was performed using software provided by PolymerChar and a CFC instrument.

[0242] In the first step, to obtain well-resolved TREF peaks for the highly crystalline fraction (HCF) and the less crystalline fraction (LCF), an a-TREF curve considering only the high molecular weight fraction was first established. Therefore, it is assumed that the polymer fraction with a molar mass log M greater than 5.2 (~158000 g / mol) can yield an a-TREF curve for the high molecular weight fraction (a-TREF (HMWF)). This is particularly advantageous if the comonomer contents of the highly crystalline and less crystalline fractions are similar, i.e., the peak temperature difference between HCF and LCF is less than 20°C.

[0243] The maximum values ​​of the HCF peak (Tp(HCF)) and LCF peak (Tp(LCF)) were determined by α-TREF(HMWF), where Tp(HCF) was higher than Tp(LCF) and less than 99°C. Figure 2 The a-TREF(HMWF) and a-TREF curves for CE2 are shown.

[0244] In the next step, Mw was measured at elution temperatures Tp(LCF) and Tp(HCF). Therefore, Mw(Mw(Tp(LCF)) at Tp(LCF) was calculated by linear interpolation between Mw values ​​at elution temperatures above and below Tp(LCF) measured by GPC. This was achieved using, for example, the "TREND" function in Excel.

[0245] The same procedure was performed to determine Mw at Tp(HCF).

[0246] Based on the Tp(LCF) of the obtained a-TREF (HMWF) curve, the full width at half maximum (FWHM) is defined as the elution temperature difference between the pre-elution temperature and the post-elution temperature at half the maximum peak height of Tp(LCF). If the interpeak separation is poor, the search starts from 35°C for the pre-elution temperature at the corresponding half-maximum value and moves forward, while the search starts from 100°C for the post-elution temperature. If LCF and HCF are well separated, the search proceeds to the post-elution temperature after HCF.

[0247] Dart Drop Intensity (DDI)

[0248] Dart dropping measurements were performed on the membranes produced as shown below using ASTM D1709 Method A (Alternative Test Technique). Darts with a hemispherical head and a diameter of 38 mm were dropped from a height of 0.66 m onto the multilayer membrane clamped in a hole. Twenty sets of samples were tested consecutively. One weight was used for each set, and the weight increased (or decreased) in uniform increments between sets. The weight that caused 50% of the samples to break was calculated and reported.

[0249] Tensile modulus

[0250] Tensile modulus (E-Mod (MPa)) was measured in accordance with ISO 527-3 on a 40 μm thick membrane sample prepared as described in the membrane sample preparation, along the longitudinal / transverse direction at a crosshead speed of 1 mm / min for modulus.

[0251] Haze

[0252] The haze of the membrane produced as shown below was measured according to ASTM D 1003-00.

[0253] Membrane sample preparation

[0254] Monolayer test membranes with a thickness of 40 μm, composed of the multimodal copolymer (P) of this invention and their respective comparative polymers, were prepared using a Collin 25 benchtop scale line. Membrane samples were produced using BUR 2.5:1. The melting temperature was 199°C, the frosting line distance was 100 mm, the screw speed was 126 rpm, and the outflow rate was 7.3 m / min.

[0255] Experimental Section

[0256] Example: Preparation of IE1 catalyst (CAT1)

[0257] SiO2 loading:

[0258] Add 10 kg of silica (PQ Corporation ES757, calcined at 600°C) from the feed hopper and inertize it in the reactor until the O2 level is below 2 ppm.

[0259] Preparation of MAO / tol / MC:

[0260] At 25°C (oil circulation temperature) and with stirring at 95 rpm, 30 wt% MAO from toluene (14.1 kg) was added from a balance to another reactor, followed by the addition of toluene (4.0 kg). After the addition of toluene, the stirring speed was increased from 95 rpm to 200 rpm for 30 minutes. 477 g of metallocene racemic dimethylsilanediylbis{2-(5-(trimethylsilyl)furan-2-yl)-4,5-dimethylcyclopentadien-1-yl}zirconium dichloride was added from a metal cylinder, followed by rinsing with 4 kg of toluene (total toluene 8.0 kg). The reactor stirring speed was changed to 95 rpm for MC feed, then returned to 200 rpm and maintained for 3 hours. After the reaction time, the MAO / tol / MC solution was transferred to a feed vessel.

[0261] Preparation of catalysts:

[0262] The reactor temperature was set to 10°C (oil circulation temperature) and the mixture was stirred at 40 rpm with MAO / tol / MC added. The MAO / tol / MC solution (target 22.5 kg, actual 22.2 kg) was added over 205 min, followed by stirring for 60 min (oil circulation temperature set to 25°C). After stirring, the "dry mixture" was stabilized at 25°C (oil circulation temperature) for 12 h with a stirring speed of 0 rpm. The reactor was rotated 20° (back and forth) and stirred several times per hour at 5 rpm.

[0263] After stabilization, the catalyst was dried at 60°C (oil circulation temperature) for 2 hours under a nitrogen flow of 2 kg / h, followed by vacuum drying for 13 hours (with the same nitrogen flow and stirring at 5 rpm). Samples of the dried catalyst were taken, and the HC content was measured using thermogravimetric analysis with a Sartorius moisture analyzer (model MA45) in a glove box. The target HC level was <2% (actual 1.3%).

[0264] Comparative catalyst (CAT2)

[0265] As catalyst CAT2, a supported catalyst containing aluminoxane was used, which contains metallocene di(1-methyl-3-n-butylcyclopentadienyl)zirconium chloride (IV) and features enhanced ActivCat® activator technology from Grace.

[0266] Polymerization: Embodiment of the present invention: The multimodal polyethylene copolymer (P) of the present invention having 1-butene and 1-hexene comonomers.

[0267] The Borstar pilot plant consists of a three-reactor unit (loop 1 – loop 2 – GPR1) and a prepolymer loop reactor.

[0268] The multimodal copolymer (P) of the present invention in Example 1 (IE1) and the multimodal copolymer (P) of the comparative example (CE1) were produced by using the polymerization conditions given in Table 1.

[0269] Table 1: Aggregation Conditions

[0270] <![CDATA[ Prepolymerization reactor ]]> catalyst CAT1 CAT2 Catalyst feed (g / h) 66.80 43.28 Temperature (°C) 50 50 Pressure (kPa) 5811 5706 C2 (kg / h) 4.0 4.0 H2(g / h) 0.69 0.04 C4 (g / h) 83.70 149.98 Split (wt%) 3,1 3,5 <![CDATA[ Ring pipe section 1 (A-1) ]]> Temperature (°C) 85 85 Pressure (kPa) 5542 5520 C2 concentration (mol%) 2.96 3.42 H2 / C2 ratio (mol / kmol) 0.43 0.42 C4 / C2 ratio (mol / kmol) 55.78 75.90 Splits (wt%) 18.2 19.0 Density (kg / m3) of material in ring pipe 1 (partial (A-1)) 940 941 MFR2 (g / 10 min) of material in loop 1 (partial (A-1)) 6.2 5.9 <![CDATA[ Ring pipe 2 ]]> Temperature (°C) 85.0 85 Pressure (kPa) 5362 5329 C2 concentration (mol%) 4.28 3.73 H2 / C2 ratio (mol / kmol) 0.31 0.06 C4 / C2 ratio (mol / kmol) 80.77 85.80 Splits (wt%) 19.2 20.0 Density (kg / m3) of component (A) after loop 2 938 942 MFR2 (g / 10 min) after loop 2 (component (A)) 6.0 7.4 MFR2 (g / 10 min) of material in loop 2 (partial (A-2)) 5.8 9.5 Density (kg / m3) of material in ring pipe 2 (partial (A-2)) 936 943 C4 (mol%) of material in loop 2 (part (A-2)) 0.74 0.47 <![CDATA[ GPR ]]> Temperature (°C) 75.0 75.0 Pressure (kPa) 2000.1 1999.9 H2 / C2 ratio (mol / kmol) 0.93 0.23 C6 / C2 ratio (mol / kmol) 9.82 34.00 Splits (wt%) 59.6 57.5 MFR2 (g / 10 min) of GPR material (component (B)) 0.4 0.5 Density (kg / m3) of GPR material (component (B)) 907.5 902.9 C6 (mol%) of GPR material (component (B)) 4.54 5.22

[0271] The polymer was mixed with 2400 ppm of Irganox B561 and 270 ppm of Dynamar FX 5922, compounded and extruded into granules using a twin-screw extruder ZSK18 under a nitrogen atmosphere; melt temperature 192°C.

[0272] Table 2: Material properties and membrane parameters of the multimodal copolymer (P) of the present invention and the comparative copolymer

[0273] <![CDATA[MFR2 (g / 10 min) (final)]]> 1.25 1.64 <![CDATA[Density (kg / m 3 )]]> 919.4 918.5 C4 (mol%) 0.3 0.2 C6 (mol%) 2.7 3.0 Mn (kg / mol) 16.7 19.85 Mw (kg / mol) 89.85 88.8 Mw / Mn 5.38 4.46 Mw(Tp(LCF) / Mw(Tp(HCF)* 2.5 1.3 Full width at half maximum (LCF) of TREF curves with LogM>5,2 9.8 21.1 Membrane properties DDI [g] 880 775 Tensile modulus (MPa) (MD / TD) 215 / 245 172 / 184 Haze 21.5 17.3 OMA 8800 7705

[0274] *: HCF: Highly crystalline fraction / LCF: Lowly crystalline fraction. CFC data.

[0275] As can be clearly seen from the table above, the film composed of the invented multimodal copolymer (P) exhibits higher DDI and tensile modulus compared to the comparative example.

[0276] In addition, such membranes have improved overall performance, namely higher OMA.

Claims

1. A metallocene-catalyzed multimodal polyethylene copolymer P, which has the following composition: (i) 35.0 to 50.0 wt% of ethylene-1-butene polymer component A, and (ii) 50.0 to 65.0 wt% of ethylene-1-hexene polymer component B, Among them, ethylene-1-butene polymer component A has Between 920 and 950 kg / m 3 Density within a certain range MFR2 measured at 190°C under a load of 2.16 kg according to the method of ISO 1133 in the range of 2.0 to 20.0 g / 10 min. Based on ethylene-1-butene polymer component A, the 1-butene content ranges from 0.1 to 2.0 mol%. The ethylene-1-butene polymer component A is composed of ethylene-1-butene polymer moiety A-1 and ethylene-1-butene polymer moiety A-2. The ethylene-1-butene polymer portion A-1 has a concentration of 920 to 960 kg / m³. 3 The density within the range of 1.0 to 15.0 g / 10 min, and the MFR2 measured at 190°C under a load of 2.16 kg according to the method of ISO 1133, and The ethylene-1-butene polymer portion A-2 has a concentration of 925 to 950 kg / m³. 3 The density within the range of 1.0 to 15.0 g / 10 min, and the MFR2 measured at 190°C under a load of 2.16 kg according to the method of ISO 1133. Ethylene-1-hexene polymer component B has Between 890 and 920 kg / m 3 Density within a certain range MFR2 measured at 190°C under a load of 2.16 kg, according to ISO 1133, in the range of 0.1 to 2.0 g / 10 min. Based on ethylene-1-hexene polymer component B, the 1-hexene content ranges from 2.5 to 10.0 mol%. Among them, multimodal polyethylene copolymer P has Between 915 and 925 kg / m 3 Density within a certain range MFR2 measured at 190°C under a load of 2.16 kg, according to ISO 1133, in the range of 1.0 to 3.0 g / 10 min. Molecular weight distribution, Mw / Mn, in the range of at least 4.6 to high 7.0, determined by GPC. The ratio of the molecular weight Mw of the low-crystallinity LCF fraction to the molecular weight Mw of the high-crystallinity HCF fraction in the range of 1.8 to 4.0, and The full width at half maximum (FWHM) of the low-crystallization portion of the TREF curve with LogM > 5.2 in the range of 5.0 to 20.

0.

2. The metallocene-catalyzed multimodal polyethylene copolymer P according to claim 1, wherein the ethylene-1-butene polymer component A is composed of ethylene-1-butene polymer portion A-1 and ethylene-1-butene polymer portion A-2. The ethylene-1-butene polymer portion A-1 has a concentration of 925 to 955 kg / m³. 3 The density within the range of 1.5 to 14.0 g / 10 min, and the MFR2 measured at 190°C under a load of 2.16 kg according to the method of ISO 1133. The ethylene-1-butene polymer portion A-2 has a concentration of 930 to 940 kg / m³. 3 The density within the range of 1.5 to 14.0 g / 10 min, and the MFR2 measured at 190 °C under a load of 2.16 kg according to the method of ISO 1133.

3. The metallocene-catalyzed multimodal polyethylene copolymer P according to claim 1 or 2, wherein the MFR2 of the ethylene-1-butene polymer component A, measured at 190°C under a load of 2.16 kg according to ISO 1133, is 2.5 to 16 g / 10 min, and The MFR2 of the ethylene-1-hexene polymer component B, measured at 190°C under a load of 2.16 kg according to ISO 1133, is 0.2 to 1.6 g / 10 min.

4. The metallocene-catalyzed multimodal polyethylene copolymer P according to claim 3, wherein the MFR2 of the ethylene-1-butene polymer component A, measured at 190°C under a load of 2.16 kg according to ISO 1133, is 3.0 to 12.0 g / 10 min.

5. The metallocene-catalyzed multimodal polyethylene copolymer P according to claim 3, wherein the MFR2 of the ethylene-1-butene polymer component A, measured at 190°C under a load of 2.16 kg according to ISO 1133, is 3.5 to 10 g / 10 min.

6. The metallocene-catalyzed multimodal polyethylene copolymer P according to claim 3, wherein the MFR2 of the ethylene-1-hexene polymer component B, measured at 190°C under a load of 2.16 kg according to ISO 1133, is 0.3 to 1.2 g / 10 min.

7. The metallocene-catalyzed multimodal polyethylene copolymer P according to claim 3, wherein the MFR2 of the ethylene-1-hexene polymer component B, measured at 190°C under a load of 2.16 kg according to ISO 1133, is 0.3 to 1.0 g / 10 min.

8. The metallocene-catalyzed multimodal polyethylene copolymer P according to claim 1, wherein the total amount of 1-butene based on the multimodal polyethylene copolymer P is in the range of 0.1 to 1.0 mol%, and Based on the multimodal polyethylene copolymer P, the total amount of 1-hexene is in the range of 1.5 to 8.0 mol%.

9. The metallocene-catalyzed multimodal polyethylene copolymer P according to claim 8, wherein the total amount of 1-butene based on the multimodal polyethylene copolymer P is in the range of 0.2 to 0.8 mol%.

10. The metallocene-catalyzed multimodal polyethylene copolymer P according to claim 8, wherein the total amount of 1-butene based on the multimodal polyethylene copolymer P is in the range of 0.2 to 0.6 mol%.

11. The metallocene-catalyzed multimodal polyethylene copolymer P according to claim 8, wherein the total amount of 1-hexene based on the multimodal polyethylene copolymer P is in the range of 2.0 to 6.0 mol%.

12. The metallocene-catalyzed multimodal polyethylene copolymer P according to claim 8, wherein the total amount of 1-hexene based on the multimodal polyethylene copolymer P is in the range of 2.2 to 4.0 mol%.

13. The metallocene-catalyzed multimodal polyethylene copolymer P according to claim 1, wherein, based on the ethylene-1-butene polymer component A, the total amount of 1-butene present in the ethylene-1-butene polymer component A is from 0.1 to 2.0 mol%, and Based on the ethylene-1-hexene polymer component B, the total amount of 1-hexene present in the ethylene-1-hexene polymer component B is 3.0 to 8.0 mol.

14. The metallocene-catalyzed multimodal polyethylene copolymer P according to claim 13, wherein, based on the ethylene-1-butene polymer component A, the total amount of 1-butene present in the ethylene-1-butene polymer component A is 0.2 to 1.6 mol.

15. The metallocene-catalyzed multimodal polyethylene copolymer P according to claim 13, wherein, based on the ethylene-1-butene polymer component A, the total amount of 1-butene present in the ethylene-1-butene polymer component A is 0.3 to 1.2 mol.

16. The metallocene-catalyzed multimodal polyethylene copolymer P according to claim 13, wherein the total amount of 1-butene present in the ethylene-1-butene polymer component A is 0.4 to 1.0 mol.

17. The metallocene-catalyzed multimodal polyethylene copolymer P according to claim 13, wherein, based on the ethylene-1-hexene polymer component B, the total amount of 1-hexene present in the ethylene-1-hexene polymer component B is 3.5 to 6.0 mol.

18. The metallocene-catalyzed multimodal polyethylene copolymer P according to claim 1, wherein the ethylene-1-butene polymer component A is present in an amount of 35.0 to 50.0 wt% based on the multimodal polyethylene copolymer P, and The ethylene-1-hexene polymer component B is present in an amount of 50.0 to 65.0 wt% based on the multimodal polyethylene copolymer P.

19. The metallocene-catalyzed multimodal polyethylene copolymer P according to claim 18, wherein the ethylene-1-butene polymer component A is present in an amount of 36.0 to 48.0 wt% based on the multimodal polyethylene copolymer P.

20. The metallocene-catalyzed multimodal polyethylene copolymer P according to claim 18, wherein the ethylene-1-butene polymer component A is present in an amount of 38.0 to 45.0 wt% based on the multimodal polyethylene copolymer P.

21. The metallocene-catalyzed multimodal polyethylene copolymer P according to claim 18, wherein the ethylene-1-hexene polymer component B is present in an amount of 52.0 to 64.0 wt% based on the multimodal polyethylene copolymer P.

22. The metallocene-catalyzed multimodal polyethylene copolymer P according to claim 18, wherein the ethylene-1-hexene polymer component B is present in an amount of 55.0 to 62.0 wt% based on the multimodal polyethylene copolymer P.

23. The metallocene-catalyzed multimodal polyethylene copolymer P according to claim 1, wherein the multimodal polyethylene copolymer P is produced in the presence of a metallocene complex of formula (II): (II) Each X is independently a halogen atom, C 1-6 -alkyl, C 1-6 -alkoxy, phenyl, or benzyl; Each Het is independently a monocyclic heteroaromatic group containing at least one heteroatom selected from O or S; L is -R'2Si-, where each R' is independently a C substituted with an alkoxy group having 1 to 10 carbon atoms. 1-20 - Hydrocarbon group or C 1-10 -alkyl; M is Ti, Zr, or Hf; Whether each R1 is the same or different is C 1-6 -alkyl or C 1-6 -alkoxy group; Each n is between 1 and 2; Whether each R2 is the same or different is C 1-6 -alkyl, C 1-6 -alkoxy or -Si(R)3 group; Each R is arbitrarily selected by 1 to 3 Cs. 1-6 -alkyl-substituted C 1-10 -alkyl or phenyl; and Each p is between 0 and 1.

24. A membrane comprising a metallocene-catalyzed multimodal polyethylene copolymer P according to any one of claims 1 to 23.

25. The membrane of claim 24, wherein the membrane comprises at least one layer comprising a metallocene-catalyzed multimodal polyethylene copolymer P, wherein the at least one layer comprises at least 50 wt% of the metallocene-catalyzed multimodal polyethylene copolymer P according to any one of claims 1 to 23.

26. The membrane of claim 25, wherein the at least one layer comprises at least 60 wt% of a metallocene-catalyzed multimodal polyethylene copolymer P according to any one of claims 1 to 23.

27. The membrane of claim 25, wherein the at least one layer comprises at least 70 wt% of a metallocene-catalyzed multimodal polyethylene copolymer P according to any one of claims 1 to 23.

28. The membrane of claim 25, wherein the at least one layer comprises at least 80 wt% of a metallocene-catalyzed multimodal polyethylene copolymer P according to any one of claims 1 to 23.

29. The membrane according to claim 24 or 25, wherein the membrane is characterized in that the dart impact strength (DDI) measured on a 40 μm monolayer test blown film according to ASTM D1709, Method A, is at least 780 g to 1500 g.

30. The membrane of claim 29, wherein the membrane is characterized in that the dart impact strength (DDI) measured on a 40 μm monolayer test blown film according to ASTM D1709, Method A, is 800 g to 1200 g.

31. The membrane according to claim 29, wherein the membrane is characterized in that the dart impact strength (DDI) measured on a 40 μm monolayer test blown film according to ASTM D1709, Method A, is 850 g to 1000 g.

32. The membrane according to claim 24, wherein the membrane is characterized by longitudinal and transverse tensile moduli in the range of >180 MPa to 350 MPa, as measured according to ISO 527-3 on a 40 μm monolayer blown film.

33. The membrane according to claim 32, wherein the membrane is characterized in that the longitudinal and transverse tensile moduli, measured according to ISO 527-3 on a 40 μm monolayer test blown film, are in the range of 200 MPa to 300 MPa.

34. The membrane of claim 24, wherein the membrane is characterized by a haze of less than 25% as measured on a 40 μm monolayer blown film according to ASTM D 1003-00.

35. The membrane of claim 34, wherein the membrane is characterized by a haze of 5% to 24% as measured on a 40 μm monolayer test blown film according to ASTM D 1003-00.

36. The membrane of claim 34, wherein the membrane is characterized by a haze of 10% to 23% as measured on a 40 μm monolayer test blown film according to ASTM D 1003-00.

37. The membrane according to claim 24, wherein the membrane is characterized according to formula (I): The photomechanical capability (OMA) is at least 7800 MPa*g / % and up to 15000 MPa*g / %, wherein the longitudinal tensile modulus (MD) is measured at 23°C on a 40 µm test blown film according to ISO 527-3, the DDI is the dart impact strength determined on a 40 µm test blown film according to ASTM D1709, Method A, and the haze is measured on a 40 µm test blown film according to ASTM D1003.

38. The membrane according to claim 37, wherein the photomechanical capability (OMA) is in the range of 8000 MPa*g / % to up to 12000 MPa*g / % 39. The membrane according to claim 37, wherein the membrane is characterized in that the photomechanical capability (OMA) is in the range of 8200 MPa*g / % to up to 10000 MPa*g / % 40. Use of the film according to any one of claims 24 to 39 as a packaging material.

41. The use according to claim 40, wherein the packaging material is used as packaging material for food and / or medical products.

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