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

[0002] The prior art mLLDPE (metallocene catalysed linear low density polyethylene) is widely used in various aspects of daily life, such as packaging, due to its excellent cost performance.

[0003] Monomodal mLLDPE is typically used for film applications. Monomodal LLDPE has for example good optical properties (like low haze), but for example the melt processing of such polymers is not satisfactory from a production point of view and can also lead to quality issues of the final product. Multimodal LLDPE with two or more different polymer components is easier to process, but for example melt homogenization of the multimodal PE can be problematic leading to non-uniform final products, which is for example evidenced by high gel content of the final product.

[0004] Multimodal mLLDPE is known in the art.

[0005] Borealis’ WO 2021009189, WO 2021009190 and WO 2021009191 disclose a process for the production of a multimodal PE polymer in the presence of a silica supported metallocene catalyst based on the metallocene complex bis(1-methyl-3-n-butylcyclopentadienyl)zirconium(IV) dichloride in two loop reactors and one gas phase reactor.

[0006] The total density of the polymers produced in the examples is 938 or 939 kg / m 3 .

[0007] There is no mention at all of film properties like tensile modulus (TM), impact strength (Dart Drop Impact, DDI) and instrumented puncture test (IPT).

[0008] WO 2021009192 discloses such a process as well. The polymers produced in the examples have an even higher density of 951 kg / m 3 .

[0009] There is no mention at all of film properties like tensile modulus (TM), impact strength (Dart Drop Impact, DDI) and instrumented puncture test (IPT).

[0010] There is an ongoing need to find multimodal PE polymers with different performance balances to provide tailored solutions to meet the growing demands of end application producers, for example to reduce production costs while maintaining or even improving the performance of the end product. There is also a need for tailored polymer solutions to meet the requirements of the evolving equipment technology in the end application fields.

[0011] Therefore, there is a need in the art to provide a material with good mechanical properties, in particular dart drop (impact strength) and instrumented puncture test (IPT).

[0012] Furthermore, the ratio of the soluble fraction (determined with Cross-Fractionation Chromatography (CFC)) to the density of such multimodal PE polymers is low, as this soluble fraction is generally problematic in certain packaging fields, for example in food packaging.

[0013] The inventors have now found that a metallocene catalysed multimodal polyethylene copolymer (P) prepared with a specific metallocene catalyst and having a specific polymer design has a very low ratio of the soluble fraction (determined with Cross-Fractionation Chromatography (CFC)) to the density.

[0014] A film made from such metallocene catalysed multimodal polyethylene copolymer (P) has an improved performance balance, in particular in terms of stiffness (i.e. tensile modulus), dart drop impact (DDI) and instrumented puncture test (IPT). SUMMARY

[0015] Therefore, the present invention relates to a metallocene catalysed multimodal polyethylene copolymer (P) consisting of (i) 35.0 to 50.0 wt% of an ethylene-1 -butene polymer component (A), and (ii) 50.0 to 65.0 wt% of an ethylene-1 -hexene polymer component (B),

[0016] wherein the ethylene-1 -butene polymer component (A) has

[0017] a density in the range of 920 to 960 kg / m 3 ,

[0018] an MFR2 (190°C, 2.16 kg, ISO 1133) in the range of 3.0 to 300.0 g / 10 min,

[0019] a 1 -butene content in the range of 0.1 to 3.0 wt% based on the ethylene-1 -butene polymer component (A);

[0020] wherein the ethylene-1 -butene polymer component (A) consists of an ethylene-1 -butene polymer fraction (A-1 ) and an ethylene-1 -butene polymer fraction (A-2),

[0021] wherein the ethylene-1 -butene polymer fraction (A-1 ) has a density in the range of 920 to 960 kg / m

[0022] The ethylene-1 -hexene polymer component (B) has

[0023] a density in the range of 880 to 920 kg / m 3 ,

[0024] an MFR2 (190°C, 2.16 kg, ISO 1133) in the range of 0.001 to 1.0 g / 10 min, based on the ethylene-1 -butene polymer compound (B), a 1 -hexene content in the range of 2.5 to 10.0 mol%,

[0025] wherein the multimodal polyethylene copolymer (P) has

[0026] a density in the range of 910 to 930 kg / m 3 ,

[0027] an MFR2 (190°C, 2.16 kg, ISO 1133) in the range of 0.1 to 1.0 g / 10 min,

[0028] a ratio of MFR 21 (190°C, 21.6 kg, ISO 1133) to MFR2 (190°C, 2.16 kg, ISO 1133) (MFR 21 / MFR2) in the range of 22 to 50, and

[0029] a ratio of the amount of the soluble fraction at 35°C to the density of the multimodal polyethylene copolymer (P) (SF@35°C / density P ) determined by cross-fractionation chromatography (CFC) as described in the experimental part is below 0.007, wherein the amount of the soluble fraction at 35°C is in the range of 0.5 to 6.0 wt%, based on the total multimodal polyethylene copolymer (P).

[0030] In one embodiment of the present application, the multimodal polyethylene copolymer (P) is further characterized by a ratio of the molecular weight (Mw) of the low crystalline fraction (LCF) to the molecular weight (Mw) of the high crystalline fraction (HCF) (Mw(Tp(LCF) / Mw(Tp(HCF)) in the range of > 1.3 to 10.0, and / or

[0031] a ratio of the half-height width (LCF) / (98-Tp(LCF)) in the range of 0.10 to 1.50, and / or

[0032] a delta value of Mw(LCF)-Mw(HCF) of at least 31000 to at most 200000 g / mol.

[0033] In another embodiment of the present application, the ethylene-1 -butene polymer component (A) of the metallocene catalysed multimodal polyethylene copolymer (P) consists of an ethylene polymer fraction (A-1 ) and an ethylene polymer fraction (A-2), wherein the density of fractions (A-1 ) and (A-2) is in the range of 925 to 960 kg / m 3 3 to 300 g / 10 min and wherein the density and / or the MFR2(190 °C, 2.16 kg, ISO 1133) of the ethylene polymer fractions (A-1 ) and (A-2) can be the same or can be different.

[0034] Surprisingly, the multimodal polyethylene copolymer (P) of the present application provides a film with improved mechanical properties, such as high instrumented puncture (IPT), high dart drop strength (DDI), and at the same time good tensile modulus.

[0035] Definitions

[0036] Where the term "comprising" or "including" is used in the specification, this term is used in the inclusive sense of "comprising" or "including" but not limited to, and allows for the possibility that other, non-specifically mentioned elements can also be present. For the purposes of the present application, the term "consisting of is considered to be a preferred embodiment of the term "comprising". If a group is defined to comprise at least an indefinite number of embodiments, this is also to be understood as disclosing a group which preferably consists only of these embodiments.

[0037] Whenever the terms "including" or "having" are used, these terms are meant to be equivalent to "comprising" as defined above.

[0038] Whenever an indefinite article is used, such as "a" or "an", or a definite article, such as "the" or "said", in reference to a singular noun, this includes a plurality of such nouns, unless otherwise indicated.

[0039] The metallocene catalysed multimodal polyethylene copolymer is defined in the present application as a multimodal polyethylene copolymer (P) which is produced in the presence of a metallocene catalyst.

[0040] In the context of the multimodal polyethylene copolymer (P), the term "multimodal" refers herein to multimodality with respect 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, the multimodal polyethylene copolymer (P) can further have multimodality with respect to one or more other properties between the ethylene polymer components (A) and (B).

[0041] The multimodal polyethylene copolymer (P) of the present application as defined above, below or in the claims is also referred to herein simply as "multimodal PE" or "multimodal copolymer (P)".

[0042] The following preferred embodiments, properties and subgroups of the multimodal PE and of its ethylene polymer components (A) and (B) and of the ethylene polymer fractions (A-1) and (A-2) of the present application, including preferred ranges thereof, are independently generalizable, so that they can be used in any order or combination to further define preferred embodiments of the multimodal PE and of the articles of the present application.

[0043] Multimodal PE and ethylene polymer components (A) and (B) and ethylene polymer fractions (A-1) and (A-2)

[0044] The metallocene-produced multimodal polyethylene copolymer (P) is referred to herein as "multimodal" because the ethylene-1 -butene polymer component (A), including the ethylene polymer fractions (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 (MFR, e.g. MFR2). That is, the multimodal PE is multimodal at least in terms of the MFR2 difference of the ethylene polymer components (A) and (B).

[0045] The metallocene-produced multimodal polyethylene copolymer (P) consists of (i) 35.0 to 50.0 wt% of an ethylene-1 -butene polymer component (A), and (ii) 50.0 to 65.0 wt% of an ethylene-1 -hexene polymer component (B).

[0046] The amounts of (A) and (B) add up to 100.0 wt%.

[0047] The ethylene-1 -butene polymer component (A) consists of the ethylene polymer fractions (A-1) and (A-2).

[0048] The MFR2 of the ethylene polymer fractions (A-1) and (A-2) can be different from each other or can be the same.

[0049] The MFR2 (190 °C, 2.16 kg, ISO 1133) of the ethylene polymer fractions (A-1) and (A-2) is in the range of 3.0 to 300.0 g / 10 min, preferably 3.5 to 250.0 g / 10 min, more preferably 4.0 to 200.0 g / 10 min, even more preferably 4.5 to 150.0 g / 10 min.

[0050] The MFR2 of the ethylene polymer components (A) and (B) is different from each other.

[0051] The MFR2(190°C, 2.16 kg, ISO 1133) of the ethylene polymer component (A) is in the range of 3.0 to 300 g / 10 min, preferably 3.5 to 250.0 g / 10 min, more preferably 4.0 to 200.0 g / 10 min, even more preferably 4.5 to 150.0 g / 10 min.

[0052] The MFR2(190°C, 2.16 kg, ISO 1133) of the ethylene polymer component (B) is in the range of 0.001 to 1.0 g / 10 min, preferably 0.005 to 0.8 g / 10 min, more preferably 0.008 to 0.6 g / 10 min, even more preferably 0.01 to 0.3 g / 10 min.

[0053] The MFR2(190°C, 2.16 kg, ISO 1133) of the multimodal copolymer (P) is in the range of 0.1 to 1.0 g / 10 min, preferably 0.2 to 0.9 g / 10 min, more preferably 0.3 to 0.8 g / 10 min.

[0054] Of course, in addition to the multimodality with respect to the MFR2of the ethylene polymer components (A) and (B) (i.e. the difference between them), the multimodal PE of the present application can also be multimodal with respect to one or both of two other properties, for example:

[0055] Multimodality with respect to the difference between:

[0056] - the comonomer content present in the ethylene polymer components (A) and (B); and / or

[0057] - the density of the ethylene polymer components (A) and (B).

[0058] Preferably, the multimodal polymer (P) is further multimodal with respect to the MFR difference of the ethylene polymer components (A) and (B).

[0059] The comonomer type of the polymer fractions (A-1) and (A-2) is the same, so both fractions have 1-butene as comonomer.

[0060] The comonomer content of the components (A) and (B) can be measured, or in the preferred case where one of the components is first produced, and then the other component is produced in the presence of the first produced component in a so-called multi-stage process, then the comonomer content of the first produced component (e.g. component (A)) can be measured, and the comonomer content of the other component (e.g. component (B)) can be calculated according to the following formula:

[0061] Comonomer content in component B (mol%) = (comonomer content in final product (mol%) - (weight fraction of component A * comonomer content in component A (mol%)) / (weight fraction of component B)

[0062] The total amount of 1 -butene based on the multimodal polymer (P) preferably ranges from 0.1 to 1.0 mol%, more preferably from 0.2 to 0.8 mol%, even more preferably from 0.3 to 0.7 mol%.

[0063] The total amount of 1 -hexene based on the multimodal polymer (P) preferably ranges from 1.5 to 8.0 mol%, more preferably from 2.0 to 6.0 mol%, even more preferably from 2.2 to 4.0 mol%.

[0064] The total amount of 1 -butene present in the ethylene-1 -butene polymer component (A) (mol%) based on the ethylene-1 -butene polymer component (A) is from 0.1 to 3.0 mol%, preferably from 0.3 to 2.6 mol%, more preferably from 0.5 to 2.0 mol%, even more preferably from 0.6 to 1.8 mol%.

[0065] The total amount of 1 -hexene present in the ethylene-1 -hexene polymer component (B) (mol%) based on the ethylene-1 -hexene polymer component (B) is from 2.5 to 10.0 mol%, preferably from 3.0 to 8.0 mol%, more preferably from 3.5 to 6.0 mol%.

[0066] Even more preferably, the multimodal polymer (P) of the present application 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, preferably higher, than the density of the ethylene polymer component (B).

[0067] The density of the ethylene polymer component (A) is in the range of from 920 to 960 kg / m 3 , preferably from 925 to 955 kg / m 3 , more preferably from 930 to 950 kg / m 3 , and / or the density of the ethylene polymer component (B) is in the range of from 880 to 920 kg / m 3 , preferably from 885 to 915 kg / m 3 , even more preferably from 890 to 910 kg / m 3 .

[0068] The density of the polymer fractions (A-1 ) and (A-2) is in the range of from 925 to 960 kg / m 3 , preferably from 928 to 955 kg / m 3 , more preferably from 930 to 950 kg / m 3most preferably 935 to 945 kg / m 3 .

[0069] The densities of the polymer fractions (A-1 ) and (A-2) can be the same or can differ from each other.

[0070] The metallocene catalysed multimodal copolymer (P) is preferably a linear low density polyethylene (LLDPE) which has the well known meaning.

[0071] The density of the multimodal copolymer (P) is in the range of 910 to 930 kg / m 3 , preferably 912.0 to 925 kg / m 3 , more preferably 915.0 to 920.0 kg / m 3 .

[0072] It is more preferred that the multimodal copolymer (P) is multimodal at least with respect to the MFR2, the comonomer content and the density of the ethylene polymer fractions (A) and (B), i.e. has differences, as defined above, below or in the claims, including any preferred ranges or embodiments of the polymer composition.

[0073] Further, the molecular weight distribution (Mw / Mn) of the multimodal copolymer (P) determined by GPC is in the range of at least 3.5 to at most 7.2, preferably in the range of 4.0 to 7.0, more preferably in the range of 4.5 to 6.8.

[0074] Further, the ratio of the soluble fraction at 35°C to the density of the multimodal polyethylene copolymer (P) (SF@35°C / density P ) is below 0.007, preferably below 0.006, more preferably below 0.005, for example in the range of 0.001 to below 0.007, preferably 0.001 to below 0.006, more preferably 0.001 to below 0.005.

[0075] The amount of the soluble fraction at 35°C is in the range of 0.5 to 6.0 wt%, preferably 0.8 to 5.0 wt%, more preferably 1.0 to 4.0 wt% based on the total multimodal polyethylene copolymer (P).

[0076] In embodiments of the present application, the multimodal copolymer (P) is further characterized by a ratio of the molecular weight (Mw) of the low crystalline fraction (LCF) to the molecular weight (Mw) of the high crystalline fraction (HCF) (Mw(Tp(LCF) / Mw(Tp(HCF)) determined as described in the experimental part is in the range of > 1.3 to 10.0, preferably in the range of 2.0 to 8.0, more preferably in the range of 2.2 to 6.0, and / or

[0077] The ratio of the half-height width (LCF) / (98-Tp(LCF)) is in the range of 0.10 to 1.50, preferably in the range of 0.15 to 1.2, more preferably in the range of 0.20 to 1.0, and / or

[0078] The delta value of Mw(LCF)-Mw(HCF) is at least 31000 up to 200000 g / mol, preferably 50000 to 180000 g / mol, more preferably 80000 to 150000 g / mol.

[0079] Preferably, the multimodal polyethylene copolymer (P) is additionally characterized by at least 2 of the above parameters, more preferably by all 3 of the above parameters.

[0080] Definition of the high crystalline fraction (HCF) and the low crystalline fraction (LCF):

[0081] The high crystalline fraction (HCF) refers to the amount of polymer fraction (in wt%) having a crystallization temperature higher than 90°C, mainly containing homogenous polyethylene chains or chains with very low content of branches.

[0082] The low crystalline fraction (LCF) refers to the amount of polymer fraction (in wt%) having a crystallization temperature in the range of 30°C to below 90°C.

[0083] Within the scope of the present application, the first and second ethylene polymer fractions (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.

[0084] The ethylene polymer component (A) is present in an amount of 35.0 to 50.0 wt%, preferably in an amount of 36.0 to 48.0 wt%, even more preferably in an amount of 38.0 to 45.0 wt%, based on the multimodal copolymer (P).

[0085] Thus, the ethylene polymer component (B) is present in an amount of 50.0 to 65.0 wt%, preferably in an amount of 52.0 to 64.0 wt%, more preferably in an amount of 55.0 to 62.0 wt%, based on the multimodal copolymer (P).

[0086] The multi-modal copolymer (P) can be produced with a three-stage process, which preferably comprises a first slurry reactor (loop reactor 1), wherein this first slurry loop reactor is connected in series to another slurry reactor (loop reactor 2), so that a first ethylene polymer fraction (A-1) produced in loop reactor 1 is fed to loop reactor 2, in which this second ethylene polymer fraction (A-2) is produced in the presence of the first fraction (A-1). Thus, loop reactor 2 is connected in series to a gas phase reactor (GPR), so that the first ethylene polymer component (A) leaving the second slurry reactor is fed to the GPR to produce a tri-modal polyethylene copolymer. In this case, the reaction conditions in the two slurry reactors are chosen so that products differing in MFR and / or density are produced in the two slurry reactors.

[0087] This process is described, inter alia, in WO 2016 / 198273, WO 2021009189, WO 2021009190, WO 2021009191 and WO 2021009192. The full details of how to make suitable metallocene-catalysed multi-modal copolymers (P) can be found in these references.

[0088] A suitable process is the Borstar PE process or the Borstar PE 3G process.

[0089] Thus, the metallocene-catalysed multi-modal copolymer (P) according to the present application is preferably produced in a loop-loop-gas phase cascade. Such a polymerisation step can be preceded by a prepolymerisation step. The purpose of the prepolymerisation is to polymerise a small amount of polymer onto the catalyst at low temperature and / or low monomer concentration. By prepolymerisation, the performance of the catalyst in the slurry and / or the properties of the final polymer can be improved. This prepolymerisation step is preferably carried out in the slurry and the amount of polymer produced in the optional prepolymerisation step is counted as the amount (wt%) of ethylene polymer component (A).

[0090] When a prepolymerisation step is present, the catalyst components are preferably introduced in their entirety into the prepolymerisation step. However, when the solid catalyst component and the co-catalyst can be fed separately, it is possible for only a part of the co-catalyst to be introduced into the prepolymerisation stage, while the remainder is introduced into the subsequent polymerisation stage. Furthermore, in this case, it is necessary to introduce so much co-catalyst into the prepolymerisation stage so as to obtain a sufficient polymerisation reaction therein.

[0091] It will be appreciated that, within the scope of the present application, the amount of polymer produced in the prepolymerisation is within 1 to 5 wt% relative to the final metallocene-catalysed multi-modal copolymer (P). This can be counted as part of the first ethylene polymer component (A).

[0092] Catalyst

[0093] The metallocene-catalyzed multimodal copolymer (P) used in the process of the present application is prepared using a metallocene catalyst. The metallocene catalyst comprises a metallocene compound and a co-catalyst. The metallocene compound or complex is also referred to herein as an organometallic compound (C).

[0094] The organometallic compound (C) comprises a transition metal (M) of Group 3 to 10 or an actinide or lanthanide element of the Periodic Table (IUPAC 2007).

[0095] According to the present application, the term "organometallic compound (C)" includes any metallocene or non-metallocene compound of a transition metal, which carries at least one organic (coordination) ligand and exhibits catalytic activity alone or together with a co-catalyst. Transition metal compounds are well known in the art and the present application encompasses compounds from Groups 3 to 10, for example Groups 3 to 7, or Groups 3 to 6, for example Groups 4 to 6, of the Periodic Table (IUPAC 2007), as well as compounds of lanthanide or actinide metals.

[0096] In one embodiment, the organometallic compound (C) has the following formula (I):

[0097]

[0098] wherein each X is independently a halogen atom, a C 1-6 -alkyl, C 1-6 -alkoxy, phenyl or benzyl;

[0099] each Het is independently a monocyclic heteroaromatic radical containing at least one heteroatom selected from O or S;

[0100] L is -R'2Si-, wherein each R' is independently a C 1-20 -hydrocarbyl or C 1-10 -alkyl;

[0101] M is Ti, Zr or Hf;

[0102] each R 1 is the same or different C 1-6 -alkyl or C 1-6 -alkoxy;

[0103] each n is 1 to 2;

[0104] each R 2 is the same or different C 1-6 -alkyl, C 1-6 -alkoxy or a -Si(R)3 radical;

[0105] each R is an optionally substituted C1-6 - alkyl-substituted C 1-10 - alkyl or phenyl; and

[0106] each p is 0 to 1.

[0107] Preferably, the compound of formula (I) has the structure

[0108]

[0109] wherein each X is independently a halogen atom, C 1-6 - alkyl, C 1-6 - alkoxy, phenyl or benzyl;

[0110] L is Me2Si-;

[0111] each R 1 are the same or different and are C 1-6 - alkyl, such as methyl or tert-butyl;

[0112] each n is 1 to 2;

[0113] R 2 is -Si(R)3alkyl; each p is 1;

[0114] each R is C 1-6 - alkyl or phenyl.

[0115] Highly preferred complexes of formula (I) are

[0116]

[0117] Most preferably, the complex dimethylsilanediylbis[2-(5- trimethylsilylfuran-2-yl)-4,5-dimethylcyclopentadien-1-yl]zirconium dichloride is used.

[0118] More preferably, the ethylene polymer components (A) and (B) of the multimodal copolymer (P) are produced using the same metallocene catalyst, i.e. in the presence of the same metallocene catalyst.

[0119] For the formation of the catalyst, a co-catalyst, also known as activator, is used. Co-catalysts comprising Al or B are well known and can be used here. Preferably, an aluminoxane (e.g. MAO) or a boron-based co-catalyst (e.g. borate) is used.

[0120] In contrast to Ziegler Natta catalysis, polyethylene copolymers produced using site catalysis have characteristics that distinguish them from Ziegler Natta materials. In particular, the comonomer distribution is more uniform. This can be shown with TREF or Crystaf techniques. Catalyst residues can also indicate the catalyst used. Ziegler Natta catalysts do not contain, for example, Group (IV) metals of Zr or Hf.

[0121] The metallocene-catalyzed multimodal copolymer (P) can contain further polymer components and optionally additives and / or fillers. In case the metallocene-catalyzed multimodal copolymer (P) contains further polymer components, the amount of the further polymer components typically varies between 3.0 and 20.0 wt%, based on the total amount of the metallocene-catalyzed multimodal copolymer (P) and the further polymer components.

[0122] The optional additives and fillers and their amounts are conventional in the field of film applications. Examples of such additives are, inter alia, antioxidants, UV stabilizers, pigments, fillers, antistatic additives, antiblocking agents, nucleating agents, acid scavengers, and processing aids.

[0123] It is to be understood here that any additive and / or filler can optionally be added in a so-called masterbatch, which comprises the respective additive and a carrier polymer. In this case, the carrier polymer is not calculated in the polymer components of the metallocene-catalyzed multimodal copolymer (P), but in the amount of the respective additive, based on the total amount of the polymer composition (100 wt%).

[0124] Film of the present application

[0125] The film of the present application comprises at least one layer comprising the metallocene-catalyzed multimodal copolymer (P). The film can be a monolayer film comprising the metallocene-catalyzed multimodal copolymer (P) or a multilayer film wherein at least one layer comprises the metallocene-catalyzed multimodal copolymer (P). The terms “monolayer film” and “multilayer film” have the well-known meaning in the art.

[0126] The layer of the monolayer or multilayer film of the present application can consist of the metallocene-catalyzed multimodal copolymer (P) itself or of a blend of the metallocene-catalyzed multimodal copolymer (P) with further polymers. In case of a blend, any further polymer is different from the metallocene-catalyzed multimodal copolymer (P) and is preferably a polyolefin. Part of the above-mentioned additives can optionally be added to the metallocene-catalyzed multimodal copolymer (P) during the film production process.

[0127] 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).

[0128] 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.

[0129] 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.

[0130] 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.

[0131] In another preferred embodiment, the membrane is non-oriented.

[0132] 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.

[0133] 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.

[0134] The membrane of the present invention is characterized by an instrumented puncture test (IPT) impact of at least 110 J / mm to 300 J / mm, preferably 115 J / mm to 250 J / mm, and more preferably 120 J / mm to 200 J / mm, as measured according to ISO D1709 on a 40 μm monolayer blown film.

[0135] Alternatively or additionally, the film of the present application is characterized by a Dart Drop Impact (DDI) of at least 1200 g up to 2500 g, preferably 1400 g to 2300 g, more preferably 1600 g to 2200 g, determined according to ASTM D1709, Method A on a 40 pm monolayer test blown film.

[0136] Furthermore, the film according to the present application has a good stiffness (tensile modulus measured according to ISO 527-3 on a 40 pm monolayer test blown film), i.e. (>160 MPa in both directions).

[0137] Thus, the film comprising the metallocene catalysed multimodal copolymer (P) can also have an elastic modulus (tensile modulus measured according to ISO 527-3 on a 40 pm monolayer test blown film) in the range of >160 MPa to 350 Mpa, preferably 180 MPa to 300 MPa in the machine direction (MD) and in the transverse direction (TD).

[0138] The present application will be further described with reference to the following non-limiting examples. DETAILED DESCRIPTION

[0139] Determination methods:

[0140] The following methods were used for the determination of the properties of the polymers (including parts and components thereof) and / or any sample preparations thereof as described in the main text or in the experimental part, unless otherwise stated in the description or experimental part.

[0141] Melt flow rate

[0142] The melt flow rate (MFR) was determined according to ISO 1133, expressed in g / 10 min. The MFR of polyethylene was determined at 190 °C. The MFR can be determined at different loads, for example 2.16 kg (MFR2), 5 kg (MFR5) or 21.6 kg (MFR21). 21 ).

[0143] Calculation of MFR2 of component B and part (A-2)

[0144] log A = x · log B + (1 - x) · log C

[0145]

[0146] For component B:

[0147] B = MFR2 of component (A)

[0148] C = MFR2 of component (B)

[0149] A = final MFR2 (mix) of the multimodal polyethylene copolymer (P)

[0150] X = weight fraction of component (A)

[0151] For part (A-2):

[0152] B = MFR2 of the first part (A-1)

[0153] C = MFR2 of the second part (A-2)

[0154] A = final MFR2 (blend) of the cyclic polymer (= component (A))

[0155] X = weight fraction of component (A)

[0156] Density

[0157] The density of the polymer is measured according to ASTM D792, method B (equilibrium density at 23 °C) on compression molded test specimens prepared according to EN ISO 1872-2 in kg / m 3 .

[0158] Comonomer content:

[0159] Quantification of microstructure by NMR spectroscopy

[0160] Quantitative nuclear magnetic resonance (NMR) spectroscopy is used to quantify the comonomer content of the polymers.

[0161] Bruker Avance III 500 NMR spectrometer operating at 500.13 and 125.76 MHz for 1 H and 13 C, respectively, quantitative 13 C{ 1 H} NMR spectra were recorded in the molten state. All spectra were recorded at 150 °C using a 7 mm magic angle spinning (MAS) probe optimised for 13 C, all pneumatic devices used nitrogen. Approximately 200 mg of material was packed into a 7 mm outer diameter d zirconia MAS rotor and spun at 4 kHz. This setup was chosen mainly for the high sensitivity required for fast identification and accurate quantification {klimke06, parkinson07, castignolles09}. Standard single pulse excitation was employed with a 3 s short cycle delay NOE {pollard 04, klimke06} and RS-HEPT decoupling scheme {fillip05, griffin07}. A total of 1024 (1 k) transients were acquired per spectrum.

[0162] Quantitative 13 C{ 1H}NMR spectra were processed, integrated, and the relevant quantitative properties were determined from the integrals. All chemical shifts are referenced internally to the bulk methylene signal at 30.00 ppm (δ+).

[0163] The amount of ethylene was quantified using the integration of the methylene (δ+) site at 30.00 ppm and taking into account the number of monomer reporting sites per monomer:

[0164] E = I δ+ / 2

[0165] The presence of isolated comonomer units was corrected based on the number of isolated comonomer units present:

[0166] Etotal = E + (3*B + 2*H) / 2

[0167] where B and H are defined for their respective comonomers. Corrections were made in a similar manner when both continuous and non-continuous comonomer incorporation was present.

[0168] Characteristic signals corresponding to the incorporation of 1-butene were observed, and the comonomer fraction was calculated as the fraction of 1-butene in the polymer relative to all monomers in the polymer:

[0169] fBtotal = Btotal / (Etotal + Btotal + Htotal)

[0170] The amount of isolated 1-butene incorporated in EEBEE sequences was quantified using the integration of the *B2 site at 39.8 ppm and taking into account the number of comonomer reporting sites per comonomer:

[0171] B = I *B2

[0172] If present, the amount of 1-butene incorporated continuously in EEBBEE sequences was quantified using the integration of the ααB2B2 site at 39.4 ppm and taking into account the number of comonomer reporting sites per comonomer: BB = 2*IααB2B2

[0173] The amount of 1-butene incorporated non-continuously in EEBBEE sequences was quantified using the integration of the ββB2B2 site at 24.6 ppm and taking into account the number of comonomer reporting sites per comonomer:

[0174] BEB = 2*IββB2B2

[0175] Since the *B2 and *βB2B2 sites for isolated (EEBEE) and non-continuously incorporated (EEBEBEE) 1-butene overlap, respectively, the total amount of isolated 1-butene incorporation was corrected based on the amount of non-continuous 1-butene present:

[0176] B = I *B2 - 2*IββB2B2

[0177] The BBB sequence was not observed. The total content of 1-butene was calculated as the sum of isolated, consecutive, and non-consecutive incorporated 1-butene:

[0178] Btotal = B + BB + BEB

[0179] The total mole fraction of 1-butene in the polymer was then calculated:

[0180] fB = Btotal / (Etotal + Btotal + Htotal)

[0181] 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:

[0182] fHtotal = Htotal / (Etotal + Btotal + Htotal)

[0183] The amount of isolated 1-hexene incorporated in EEHEE sequences was quantified using the integration of the *B4 site at 38.3 ppm and accounting for the number of comonomer reporting sites:

[0184] H = I *B4

[0185] The amount of consecutive 1-hexene incorporated in EEHHEE sequences was quantified using the integration of the ααB4B4 site at 40.5 ppm and accounting for the number of comonomer reporting sites if present:

[0186] HH = 2 * IααB4B4

[0187] The amount of non-consecutive 1-hexene incorporated in EEHEHEE sequences was quantified using the integration of the ββB4B4 site at 24.7 ppm and accounting for the number of comonomer reporting sites if present:

[0188] HEH = 2 * IββB4B4

[0189] The HHH sequence was not observed. The total content of 1-hexene was calculated as the sum of isolated, consecutive, and non-consecutive incorporated 1-hexene:

[0190] Htotal = H + HH + HEH

[0191] The total mole fraction of 1-hexene in the polymer was then calculated:

[0192] fH = Htotal / (Etotal + Btotal + Htotal)

[0193] The mole percent of comonomer incorporation was calculated from the mole fraction:

[0194] B [wt%] = 100 * (fB * 56.11) / ((fB * 56.11) + (fH * 84.16) + ((1 - (fB + fH)) * 28.05))

[0195] H [wt%] = 100 * (fH * 84.16) / ((fB * 56.11) + (fH * 84.16) + ((1 - (fB + fH)) * 28.05))

[0196] The weight percent of comonomer incorporation is calculated from the mole fraction:

[0197] B [wt%] = 100 * (fB * 56.11) / ((fB * 56.11) + (fH * 84.16) + ((1 - (fB + fH)) * 28.05))

[0198] H [wt%] = 100 * (fH * 84.16) / ((fB * 56.11) + (fH * 84.16) + ((1 - (fB + fH)) * 28.05))

[0199] References:

[0200] Klimke, K., Parkinson, M., Piel, C, Kaminsky, W., Spiess, H. W., Wilhelm, M., Macromol. Chem. Phys. 2006; 207: 382.

[0201] Parkinson, M., Klimke, K., Spiess, H. W., Wilhelm, M., Macromol. Chem. Phys. 2007; 208: 2128.

[0202] Pollard, M., Klimke, K., Graf, R., Spiess, H. W., Wilhelm, M., Sperber, O., Piel, C, Kaminsky, W., Macromolecules 2004; 37: 813.

[0203] Filip, X., Tripon, C, Filip, C, J. Mag. Resn. 2005, 176, 239

[0204] Griffin, J. M., Tripon, C, Samoson, A., Filip, C, and Brown, S. P., Mag. Res. in Chem. 2007 45, S1, S198

[0205] Castignolles, P., Graf, R., Parkinson, M., Wilhelm, M., Gaborieau, M., Polymer 50 (2009) 2373

[0206] Busico, V., Cipullo, R., Prog. Polym. Sci. 26 (2001) 443

[0207] Busico, V., Cipullo, R., Monaco, G., Vacatello, M., Segre, A. L., Macromoleucles 30 (1997) 6251

[0208] Zhou, Z., Kuemmerle, R., Qiu, X., Redwine, D., Cong, R., Taha, A., Baugh, D. Winniford, B., J. Mag. Reson. 187 (2007) 225

[0209] Busico, V., Carbonniere, P., Cipullo, R., Pellecchia, R., Severn, J., Talarico, G., Macromol. Rapid Commun. 2007, 28, 1128

[0210] Resconi, L., Cavallo, L., Fait, A., Piemontesi, F., Chem. Rev. 2000, 100, 1253

[0211] Molecular weight, molecular weight distribution, Mn, Mw, MWD:

[0212] Molecular weight averages (Mz, Mw, and Mn), molecular weight distribution (MWD) and its breadth described by polydispersity index (PDI = Mw / Mn, where Mn is the number average molecular weight and Mw is the weight average molecular weight) are determined according to ASTM D 6474-12 using gel permeation chromatography (GPC) using the following equations:

[0213]

[0214]

[0215]

[0216] for a constant elution volume interval ΔVi, where Ai and Mi are the chromatographic peak slice area and polyolefin molecular weight (MW) associated with elution volume (Vi), respectively, where N is equal to the number of data points obtained from the chromatogram between the integration limits.

[0217] High-temperature GPC instruments equipped with infrared (IR) detectors (PolymerChar (Valencia, Spain) IR4 or IR5) or Agilent Technologies differential refractometers (RI) 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.

[0218] The column assembly was calibrated using a universal calibration method with 19 narrow MWD polystyrene (PS) standards ranging from 0.5 kg / mol to 11500 kg / mol. 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 constants:

[0219] K PS =19 x 10 -3 mL / g, α PS =0.655

[0220] K PE =39 x 10 -3 mL / g, α PE =0.725

[0221] The calibration data were fitted using a third-order polynomial fitting method.

[0222] All samples were prepared at concentrations ranging from 0.5 to 1 mg / ml. For PE, the solution was dissolved at 160°C for 3 hours with gentle shaking.

[0223] Determination of chemical heterogeneity by cross-fractional chromatography (CFC)

[0224] The chemical composition distribution and molecular weight distribution, and the corresponding average molecular weights (Mn, Mw, and Mv) at a given elution temperature (polymer crystallinity in solution) were determined by fully automated cross-fractional chromatography (CFC), as described in Ortin A., Monrabal B., Sancho-Tello J., Macromol. Symp., 2007, 257, 13-28.

[0225] Cross fractionation (TREF x SEC) was performed using a CFC instrument (PolymerChar, Valencia, Spain). Concentration was monitored using a four-waveband IR5 infrared detector (PolymerChar, Valencia, Spain). About 40 mg of polymer sample was dissolved in 25 ml TCB at 150 °C for 150 minutes in a stainless steel vessel. After complete dissolution of the sample, a 0.5 ml aliquot was loaded into the TREF column and stabilized at 110 °C for 60 minutes. The polymer was crystallized and precipitated by cooling at a constant cooling rate of 0.1 °C / min to 30 °C. The following temperature steps were used for the discontinuous elution process: (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)

[0226] In the second dimension, GPC analysis used 3x PL Olexis columns and 1x Olexis Guard column from Agilent (Church Stretton, UK) as stationary phase. 1,2,4-Trichlorobenzene (TCB, stabilized with 250 mg / L 2,6-Di-tert-butyl-4-methyl-phenol) was used as eluent at 150 °C at a constant flow rate of 1 mL / min. The column set was calibrated using universal calibration (according to ISO 16014-2:2003) with at least 15 narrow MWD polystyrene (PS) standards in the range of 0.5 kg / mol to 11500 kg / mol. The following Mark Houwink constants were used to convert PS molecular weight equivalents to PE molecular weight equivalents.

[0227] K PS = 19 x 10 -3 mL / g, a PS = 0.655

[0228] K PE = 39 x 10 -3 mL / g, a PE = 0.725

[0229] The calibration data were fitted using a third order polynomial fit. Data treatment of the CFC instrument was performed using software provided by PolymerChar.

[0230] Soluble fraction SF @ 35 °C

[0231] Soluble fraction @ 35 °C is the polymer fraction eluted at 35 °C

[0232] Mw(Tp(LCF), Mw(Tp(HCF), half width Tp(LCF), half width Tp(HCF)

[0233] To determine the weight average molecular weight at the peak maximum of the low crystalline fraction or the high crystalline fraction (Mw(Tp(LCF)) and Mw(Tp(HCF))) and the half width Tp(LCF) and Tp(HCF) in the first step, the a-TREF curve from the CFC analysis as described above is taken.

[0234] From the a-TREF curve, the maximum peak value of the high crystalline fraction (HCF) peak and the low crystalline fraction (LCF) peak (Tp(HCF) and Tp(LCF)) is determined. The elution temperature of Tp(HCF) is higher than Tp(LCF) and lower than 99°C. Typically, the high crystalline fraction is in the range of 90°C to 99°C and the low crystalline fraction is the polymer fraction eluting from 35°C to 90°C. In Figure 1 In Figure 2, the a-TREF from the CFC analysis of IE1 and CE1 is shown.

[0235] The half width of HCF and LCF is defined as the difference in elution temperature between the front end temperature and the back end temperature at half the maximum peak height, respectively Tp(LCF) or Tp(HCF). If the separation between the peaks is not good, the front temperature is searched from 35°C onwards and the back temperature at half the maximum is searched from 100°C backwards. If the LCF is well separated from the HCF, the back temperature is searched after the HCF.

[0236] In the next step, the Mw at the Tp(LCF) and Tp(HCF) elution temperature is determined. Therefore, the Mw at Tp(LCF) (Mw(Tp(LCF)) is calculated by linear interpolation between the Mw values of the GPC measurement at elution temperatures higher than Tp(LCF) and lower than Tp(LCF). This is achieved by using the "TREND" function in Excel, for example. The same procedure is used to determine the Mw at Tp(HCF).

[0237] From the determined Mw(Tp(LCF), Mw(Tp(HCF), half width (LCF) and half width (HCF) and Tp(LCF), the following parameters can be directly calculated:

[0238] Mw(Tp(LCF) / Mw(Tp(HCF)

[0239] Mw(Tp(LCF) - Mw(Tp(HCF) (g / mol) = Mw(Tp(LCF) - Mw(Tp(HCF) [g / mol]

[0240] Half width (LCF) / (98°C - Tp(LCF))

[0241] Tensile modulus

[0242] Tensile modulus (E-Mod (MPa) was measured according to ISO 527-3 on film samples of 40 pm thickness prepared as described in film sample preparation, at a crosshead speed of 1 mm / min in the machine and / or transverse direction.

[0243] Instrumented puncture impact (IPT)

[0244] Instrumented puncture impact was determined by the free-falling dart impact method (ISO 7765 - second part). The maximum force, deformation at maximum force, energy at maximum force, puncture deformation and puncture energy were determined according to ISO 7765-2 in the instrumented puncture impact behavior test. Films were blown to a thickness of 40 micrometers. The test conditions used were: impact speed of 4.4 m / s (or other), an un-lubricated striker needle of 20 mm diameter, at 23 ± 2 °C (or at other temperatures consistently ± 2 °C). The specimen was clamped with a support ring of 40 mm diameter.

[0245] Dart drop strength (DDI)

[0246] Dart drop measurements were performed on films produced as shown below using ASTM D1709 Method A (Alternative Test Technique). A dart with a hemispherical head of 38 mm diameter was dropped from a height of 0.66 m onto a multilayer film clamped over an aperture. Twenty sets of specimens were tested in succession. One weight was used per set, and the weight was increased (or decreased) in even increments from set to set. The weight that resulted in 50% sample failure was calculated and reported.

[0247] Film sample preparation

[0248] Single layer test films of 40 pm thickness consisting of the inventive multimodal copolymer (P) and the corresponding comparative polymers were prepared using a W&H semi-commercial production line. The film samples were produced at a BUR 1 :3. Melt temperature ~ 222 °C, frost line distance 700 mm, screw rotation speed 94 rpm, flow out speed 18.8 m / min.

[0249] Experimental part

[0250] Cat. Example: Catalyst (CAT1) preparation of the inventive example

[0251] Loading of SiO2:

[0252] 10 kg of silica (PQ Corporation ES757, calcined at 600 °C) was added from a feed tank and inertized in the reactor until the O2 level reached below 2 ppm.

[0253] Preparation of MAO / tol / MC:

[0254] Into another reactor, 30 wt% MAO in toluene (14.1 kg) was added from the balance, followed by toluene (4.0 kg) at 25 °C (oil bath temperature) and 95 rpm agitation. After the addition of toluene, the agitation speed was increased from 95 rpm to 200 rpm for 30 min. The metallocene rac-dimethylsilanediyl bis{2-(5-(trimethylsilyl)furan-2-yl)-4,5-dimethylcyclopentadien-1-yl}zirconium dichloride 477 g was added from the metal cylinder, followed by a rinse with 4 kg toluene (total toluene 8.0 kg). The reactor agitation speed was changed to 95 rpm for MC feeding, back to 200 rpm and for 3 h reaction time. After the reaction time, the MAO / tol / MC solution was transferred to the feed vessel.

[0255] Preparation of catalyst:

[0256] The reactor temperature was set to 10 °C (oil bath temperature) and agitated at 40 rpm for the addition of MAO / tol / MC. The MAO / tol / MC solution was added over 205 min (target 22.5 kg, actual 22.2 kg), followed by a 60 min agitation time (oil bath temperature set to 25 °C). After agitation, the “dry mix” was allowed to stabilize for 12 h at 25 °C (oil bath temperature) with 0 rpm agitation. The reactor was turned 20° (back and forth) and agitated a few rounds per hour at 5 rpm.

[0257] After stabilization, the catalyst was dried at 60 °C (oil bath temperature) under a nitrogen flow of 2 kg / h for 2 hours, followed by 13 hours under vacuum (same nitrogen flow with 5 rpm agitation). The dried catalyst was sampled and the HC content was measured in the glovebox using a Sartorius moisture analyser (model MA45) using thermogravimetry. The target HC level was < 2% (actual 1.3%).

[0258] Catalyst of the comparative example (CAT2)

[0259] As catalyst CAT2, a supported catalyst containing aluminoxane was used, which contained the metallocene bis(1-methyl-3-n-butylcyclopentadienyl)zirconium(IV) chloride and had enhanced activator technology from Grace.

[0260] Polymerization: Inventive examples: Inventive multimodal polyethylene copolymers (P) with 1-butene and 1-hexene comonomer (IE1 to IE3) and comparative example (CE1)

[0261] The Borstar pilot plant has a three reactor setup (Loop 1 - Loop 2 - GPR1) and a prepolymerization loop reactor.

[0262] The inventive multimodal copolymers (P) of examples 1-3 (IE1 to IE3) as well as the inventive multimodal copolymer (P) of comparative example (CE1) were produced by using the polymerization conditions given in table 1.

[0263]

[0264]

[0265]

[0266] The IE to IE3 and CE1 polymers were mixed with 2400 ppm of Irganox B561 and 270 ppm of Dynamar FX 5922, compounded and extruded into pellets by using a twin screw extruder ZSK18 under nitrogen atmosphere; melt temperature 192°C.

[0267] Table 2: Material properties and film parameters of the inventive multimodal copolymers (P) and comparative copolymers

[0268]

[0269] *: HCF: high crystalline fraction / LCF: low crystalline fraction. CFC data.

[0270] From the above table it is clear that the films consisting of the inventive multimodal copolymers (P) show significantly higher DDI, higher IPT impact and tensile modulus compared to the comparative examples.

[0271] Furthermore, the inventive polymers also have the advantageous low SF@35°C / density P .

Claims

1. A metallocene-catalyzed multimodal polyethylene copolymer (P), which comprises the following: (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), The ethylene-1-butene polymer component (A) has Between 920 and 960 kg / m 3 Density within a certain range MFR2 was determined at 190°C under a load of 2.16 kg, according to the method of ISO 1133, within the range of 4.5 to 150.0 g / 10 min. Based on the ethylene-1-butene polymer component (A), the 1-butene content ranges from 0.1 to 3.0 mol%. 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). Ethylene-1-hexene polymer component (B) has Between 880 and 920 kg / m 3 Density within a certain range MFR2 was determined at 190°C under a load of 2.16 kg in the range of 0.001 to 1.0 g / 10 min, according to the method of ISO 1133. Based on the ethylene-1-butene polymer compound (B), the 1-hexene content is in the range of 2.5 to 10.0 mol%. Among them, multimodal polyethylene copolymer (P) has Between 910 and 930 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 0.1 to 1.0 g / 10 min. MFR measured at 190°C under a load of 21.6 kg according to the method of ISO 1133 in the range of 22 to 50. 21 The ratio of MFR2 to the MFR measured at 190°C under a load of 2.16 kg according to ISO 1133 method, MFR 21 / MFR2, and The ratio of the soluble fraction at 35°C to the density of the multimodal polyethylene copolymer (P), determined by cross-fractional chromatography (CFC) at a concentration below 0.007, SF@35°C / density P The amount of the soluble portion at 35°C, based on the total multimodal polyethylene copolymer (P), is in the range of 0.5 to 6.0 wt%.

2. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 1, wherein the multimodal polyethylene copolymer (P) is further characterized in that the ratio of the molecular weight (Mw) of the low-crystallinity fraction (LCF) to the molecular weight (Mw) of the high-crystallinity fraction (HCF), Mw(Tp(LCF) / Mw(Tp(HCF)), is in the range of >1.3 to 10.0, and / or The ratio of half-maximum width at half maximum (LCF) / (98-Tp(LCF)) is in the range of 0.10 to 1.50, and / or The Δ value of Mw(LCF)–Mw(HCF) is at least 31000 and at most 200000 g / mol.

3. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 1 or 2, wherein portions (A-1) and (A-2) have a density of 925 to 960 kg / m³. 3 Within the range of ISO 1133, the MFR2 measured at 190°C under a load of 2.16 kg is in the range of 4.5 to 150.0 g / 10 min and the densities of the ethylene polymer portions (A-1) and (A-2) and / or the MFR2 measured at 190°C under a load of 2.16 kg are the same or different.

4. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 1 or 2, wherein the MFR2 of the ethylene polymer component (B), determined according to ISO 1133 at 190°C under a load of 2.16 kg, is 0.005 to 0.8 g / 10 min.

5. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 4, wherein the MFR2 of the ethylene polymer component (B), determined according to ISO 1133 at 190°C under a load of 2.16 kg, is 0.008 to 0.6 g / 10 min.

6. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 4, wherein the MFR2 of the ethylene polymer component (B), determined according to ISO 1133 at 190°C under a load of 2.16 kg, is 0.01 to 0.3 g / 10 min.

7. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 1 or 2, 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%.

8. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 7, 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%.

9. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 7, wherein the total amount of 1-butene based on the multimodal polyethylene copolymer (P) is in the range of 0.3 to 0.7 mol%.

10. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 7, 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%.

11. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 7, 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%.

12. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 1 or 2, wherein, 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 from 0.3 to 2.6 mol%, and / or 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 in the range of 3.0 to 8.0 mol%.

13. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 12, wherein, 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 0.5 to 2.0 mol%.

14. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 12, wherein, 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 0.6 to 1.8 mol.

15. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 12, 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 in the range of 3.5 to 6.0 mol%.

16. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 1 or 2, wherein the ethylene 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 polymer component (B) is present in an amount of 50.0 to 65.0 wt% based on the multimodal polyethylene copolymer (P).

17. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 16, wherein the ethylene polymer component (A) is present in an amount of 36.0 to 48.0 wt% based on the multimodal polyethylene copolymer (P).

18. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 16, wherein the ethylene polymer component (A) is present in an amount of 38.0 to 45.0 wt% based on the multimodal polyethylene copolymer (P).

19. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 16, wherein the ethylene polymer component (B) is present in an amount of 52.0 to 64.0 wt% based on the multimodal polyethylene copolymer (P).

20. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 16, wherein the ethylene polymer component (B) is present in an amount of 55.0 to 62.0 wt% based on the multimodal polyethylene copolymer (P).

21. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 1 or 2, wherein the multimodal polyethylene copolymer (P) is produced in the presence of a metallocene complex of formula (I): 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; Each R 1 Same or different, is C 1-6 -alkyl or C 1-6 -alkoxy group; Each n is between 1 and 2; Each R 2 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.

22. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 1 or 2, wherein the ratio of the soluble portion of the multimodal polyethylene copolymer (P) at 35°C to the density of the multimodal polyethylene copolymer (P), SF@35°C / density P , less than 0.006, and among them Based on the total multimodal polyethylene copolymer (P), the amount of the soluble portion at 35°C is in the range of 0.8 to 5.0 wt%.

23. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 22, wherein the ratio of the soluble portion of the multimodal polyethylene copolymer (P) at 35°C to the density of the multimodal polyethylene copolymer (P), SF@35°C / density P It is less than 0.

005.

24. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 22, wherein the ratio of the soluble portion of the multimodal polyethylene copolymer (P) at 35°C to the density of the multimodal polyethylene copolymer (P), SF@35°C / density P It is in the range of 0.001 to below 0.

006.

25. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 22, wherein the ratio of the soluble portion of the multimodal polyethylene copolymer (P) at 35°C to the density of the multimodal polyethylene copolymer (P), SF@35°C / density P It is in the range of 0.001 to less than 0.

005.

26. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 22, wherein the amount of the soluble portion at 35°C, based on the total multimodal polyethylene copolymer (P), is in the range of 1.0 to 4.0 wt%.

27. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 2, wherein 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 polyethylene copolymer (P), Mw(Tp(LCF) / Mw(Tp(HCF)), is in the range of 2.0 to 8.0, and / or The ratio of half-maximum width at half maximum (LCF) / (98-Tp(LCF)) is in the range of 0.15 to 1.2, and / or The Δ value of Mw(LCF)-Mw(HCF) is in the range of 50,000 to 180,000 g / mol.

28. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 27, wherein 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 polyethylene copolymer (P), Mw(Tp(LCF) / Mw(Tp(HCF)), is in the range of 2.2 to 6.

0.

29. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 27, wherein the ratio of half-maximum width at half maximum (LCF) / (98-Tp(LCF)) is in the range of 0.20 to 1.

0.

30. The metallocene-catalyzed multimodal polyethylene copolymer (P) according to claim 27, wherein the Δ value of Mw(LCF)-Mw(HCF) is in the range of 80,000 to 150,000 g / mol.

31. A membrane comprising a metallocene-catalyzed multimodal polyethylene copolymer (P) according to any one of claims 1 to 30.

32. The membrane of claim 31, 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 30.

33. The membrane of claim 31, 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 60 wt% of the metallocene-catalyzed multimodal polyethylene copolymer (P) according to any one of claims 1 to 30.

34. The membrane of claim 31, 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 70 wt% of the metallocene-catalyzed multimodal polyethylene copolymer (P) according to any one of claims 1 to 30.

35. The membrane of claim 31, 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 80 wt% of the metallocene-catalyzed multimodal polyethylene copolymer (P) according to any one of claims 1 to 30.

36. The membrane according to claim 31 or 32, wherein the membrane is characterized by an instrumented puncture test (IPT) impact of at least 110 J / mm to 300 J / mm as determined according to ISO 7765-2 on a 40 μm monolayer blown film, and / or According to ASTM D1709, Method A determines the dart impact strength (DDI) on a 40 μm monolayer blown film at a minimum of 1200 g and a maximum of 2500 g.

37. The membrane according to claim 36, wherein the membrane is characterized by an instrumented puncture test (IPT) impact of 115 J / mm to 250 J / mm as measured according to ISO 7765-2 on a 40 μm monolayer test blown film.

38. The membrane according to claim 36, wherein the membrane is characterized by an instrumented puncture test (IPT) impact of 120 J / mm to 200 J / mm as measured according to ISO 7765-2 on a 40 μm monolayer test blown film.

39. The membrane according to claim 36, 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 1400 g to 2300 g.

40. The membrane of claim 36, wherein the membrane is characterized by a dart impact strength (DDI) of 1600g to 2200g as determined by Method A of ASTM D1709 on a 40μm monolayer test blown film.

41. The membrane according to claim 31 or 32, wherein the membrane is characterized in that the elastic modulus in the longitudinal (MD) and transverse (TD) directions, measured according to the method of ISO 527-3 on a 40 μm monolayer test blown film, is in the range of >160 MPa to 350 MPa.

42. The membrane according to claim 41, wherein the membrane is characterized in that the elastic modulus in the longitudinal (MD) and transverse (TD) directions, measured according to the method of ISO 527-3 on a 40 μm monolayer test blown film, is in the range of 180 MPa to 300 MPa.

43. Use of the film according to any one of claims 31 to 42 as a packaging material.

44. Use of the film according to any one of claims 31 to 42 as a packaging material for food and / or medical products.

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