Polyethylene composition for film layers
By using a blend of multimodal linear low-density polyethylene catalyzed by metallocene and HDPE recyclable, the problems of insufficient mechanical properties of membranes and limited use of plastics in the prior art are solved, and film preparation with high stiffness and impact resistance are achieved.
Patent Information
- Application Number
- CN202380070783.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2022-10-05
- Filing Date
- 2023-09-21
- Publication Date
- 2025-05-13
AI Technical Summary
The prior art is difficult to produce films with good mechanical properties, especially in terms of stiffness and impact resistance, and the amount of recycled plastics used in the composition is limited.
A blend of multimodal linear low-density polyethylene (mLLDPE) catalyzed with metallocene catalyzed and HDPE recyclables improves the performance balance of the membrane through specific polymer design and catalyst use.
Good mechanical properties of the membrane are achieved, including high stiffness and impact resistance, while allowing for higher amounts of recyclables to be added to the composition.
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Abstract
Description
[0001] The present invention relates to a composition comprising metallocene-catalyzed multimodal linear low density polyethylene (mLLDPE) and HDPE recyclate, the use of the composition in film applications and a film comprising the polymer composition of the invention.
[0002] Polyolefins, especially polyethylene and polypropylene, are increasingly consumed in large quantities in a wide range of applications including packaging of food and other goods.
[0003] Polyethylene-based materials are a particular problem, as these are widely used in packaging. Considering the huge amounts of waste collected compared to the amount of waste recycled into the stream, there is still great potential for the intelligent reuse of plastic waste streams and for the mechanical recycling of plastic waste.
[0004] Therefore, it is important to form a circular economy that gives plastic waste a second life, i.e. recycling it. This not only prevents plastic waste from remaining in the environment, but also restores its value.
[0005] In addition, the European Commission confirmed in 2017 that it would focus on plastic production and use. The EU's goals are: 1) by 2025, at least 55% of all plastic packaging in the EU should be recycled; 2) by 2030, all plastic packaging on the EU market should be reusable or easily recyclable. This has prompted brand owners and plastic converters to seek solutions using recyclables or a mix of virgin / recyclables.
[0006] Therefore, incorporating polymers obtained from waste into the manufacture of new products is becoming increasingly important, i.e. where waste plastics, such as post-consumer recyclate (PCR), can be transformed into a resource for new plastic products. Thus, environmental and economic aspects can be combined when recycling and reusing waste plastic materials.
[0007] However, recycled plastics are often of lower quality than virgin plastics due to degradation, contamination and mixing of different plastics.
[0008] In addition, compositions containing recycled polyolefin materials generally have properties that are much worse than those of virgin materials, unless the amount of recycled polyolefin added to the final composition is extremely low. For example, such materials generally have limited impact strength and poor mechanical properties, and therefore, they cannot meet consumer requirements.
[0009] Mixing recycled plastic with virgin plastic is a common practice to improve the quality of recycled plastic.
[0010] Based on this, it is an object of the present invention to provide a polyethylene-based composition allowing the use of recycled HDPE, which can be used to produce films having good properties, in particular good mechanical properties such as impact resistance and stiffness.
[0011] Furthermore, it should be possible to add higher amounts of recyclables to the composition.
[0012] The present inventors have now found that blends of metallocene-catalyzed multimodal linear low density polyethylene (mLLDPE) prepared with specific metallocene catalysts and having a specific polymer design with HDPE recyclate (i.e. polyethylene recycled blends) provide films with an improved balance of properties, particularly in terms of stiffness (i.e. tensile modulus) and impact resistance, such as dart impact strength. Summary of the invention
[0013] The present invention therefore relates to a composition comprising
[0014] (I) 1.0 to 49.0 wt% of a metallocene-catalyzed multimodal linear low density polyethylene (mLLDPE), based on the total weight of the composition, the metallocene-catalyzed multimodal linear low density polyethylene (mLLDPE) consisting of
[0015] (i) 30.0 to 70.0 wt% of an ethylene-1-butene polymer component (A) based on the total weight of mLLDPE and
[0016] (ii) 70.0 to 30.0 wt% of an ethylene-1-hexene polymer component (B) based on the total weight of the mLLDPE, wherein the ethylene-1-butene polymer component (A) has
[0017] ·925 to 960 kg / m 3 Density in the range of 1.0 to 100.0 g / 10 min (190°C, 2.16 kg, ISO 1133),
[0018] The ethylene-1-hexene polymer component (B) has
[0019] 880 to 915 kg / m 3 range (ISO 1183) and MFR2 (190°C, 2.16 kg, ISO 1133) in the range of 0.001 to 1.0 g / 10 min, and
[0020] mLLDPE has
[0021] @910 to 925 kg / m 3 Density in the range (ISO 1183),
[0022] @MFR2 (190°C, 2.16kg, ISO 1133) in the range of 0.1 to 2.0 g / 10 min, and
[0023] @MFR in the range of 5.0 to 75.0 g / 10min 21 (190℃, 21.6kg, ISO 1133),
[0024] as well as
[0025] @MFR in the range of 15.0 to 60.0 21 / MFR2 ratio; and
[0026] (II) 51.0 to 99.0 wt% of a polyethylene recycled blend (PCR), based on the total weight of the composition, having
[0027] (i) MFR5 (ISO 1133, 5.0 kg; 190° C.) of 0.1 to 10.0 g / 10 min, and
[0028] (ii) 950 to 970 kg / m 3 density (ISO1183), and
[0029] (iii) a C2 fraction in an amount higher than 95.0 wt% as measured by NMR of the d2-tetrachloroethylene soluble fraction, and (iv) a PCR-based homopolymer fraction (HPF) content in the range of 80.0 to 91.0 wt% as determined by chemical composition analysis by cross fractionation chromatography (CFC), and (v) a PCR-based copolymer fraction (CPF) content in the range of 9.0 to 20.0 wt% as determined by chemical composition analysis by cross fractionation chromatography (CFC), and (vi) optionally a PCR-based copolymer fraction (CPF) content in the range of 10.0 to 25.0 wt% as determined by chemical composition analysis by cross fractionation chromatography (CFC). % in the range of 0.0 to 2.0 wt % based on PCR, wherein the iso-PP fraction (IPPF) is defined as the polymer fraction eluting at a temperature of 104°C and above, wherein the homopolymer fraction (HPF), the copolymer fraction (CPF) and the iso-PP fraction (IPPF) add up to 100 wt %, and (vii) 0.01 to 2.00 wt % inorganic residues (measured by TGA) relative to the total polyethylene recycled blend, and (viii) 10 m 2 OCS gels having a size of 100 to 299 microns measured in the range of 500 to 5000 counts / square meter; wherein
[0030] (ix) CIELAB color space (L * a * b * )for
[0031] -L * 75.0 to 86.0;
[0032] -a * -5.0 to 0.0;
[0033] -b * 5.0 to less than 25.0
[0034] or
[0035] (x) CIELAB color space (L * a * b * )for
[0036] -L * Above 86.0 to 97.0;
[0037] -a * -5.0 to 0.0;
[0038] -b * 0.0 to less than 5.0.
[0039] In one embodiment of the present invention, the ethylene-1-butene polymer component (A) of the metallocene-catalyzed multimodal linear low density polyethylene (mLLDPE) consists of an ethylene polymer fraction (A-1) and an ethylene polymer fraction (A-2), wherein the density (ISO 1133) of fractions (A-1) and (A-2) is in the range of 925 to 960 kg / m 3 range and MFR2 (190°C, 2.16 kg, ISO 1133) is in the range of 1.0 to 150.0 g / 10 min, and the density and / or MFR2 (190°C, 2.16 kg, ISO 1133) of the ethylene polymer parts (A-1) and (A-2) may be the same or different.
[0040] Unexpectedly, such compositions provide films having an excellent combination of stiffness and impact resistance (ie, tensile modulus and dart drop strength).
[0041] The present invention therefore further relates to a film comprising at least one layer comprising the composition according to the invention.
[0042] The specific design of the metallocene-catalyzed multimodal linear low density polyethylene (mLLDPE) thus allows for the addition of more recyclables and still provides a film with a good impact / stiffness balance.
[0043] definition
[0044] Where the term "comprising" is used in the present description and claims, it does not exclude other, not specifically stated, elements of major or minor functional importance. For the purposes of the present invention, the term "consisting of" is considered to be a preferred embodiment of the term "comprising". If a group is defined hereinafter as comprising at least a certain number of embodiments, this is also to be understood as disclosing the group, which preferably consists only of these embodiments.
[0045] Whenever the terms "including" or "having" are used, these terms are meant to be equivalent to "comprising" as defined above.
[0046] When an indefinite or definite article is used when referring to a singular noun, for example "a", "an" or "the", this includes a plural of that noun unless otherwise stated.
[0047] Metallocene-catalyzed multimodal polyethylene is defined in the present invention as a multimodal polyethylene prepared in the presence of a metallocene catalyst with at least two different comonomers selected from alpha-olefins having from 4 to 10 carbon atoms.
[0048] In contrast to Ziegler Natta catalysis, polyethylene polymers produced in the presence of metallocene catalysts have characteristics that distinguish them from Ziegler Natta materials. In particular, the comonomer distribution is more uniform. This can be shown using TREF or Crystaf techniques. Catalyst residues can also be indicative of the catalyst used. For example, Ziegler Natta catalysts do not contain Zr or Hf Group (IV) metals.
[0049] For the purposes of the present invention, "linear low density polyethylene (LLDPE) comprising a polyethylene component (A) and a polyethylene component (B)" means that the LLDPE is produced in at least a two-stage sequential polymerization process, wherein component (A) is produced first and then, in a subsequent polymerization step, component (B) is produced in the presence of component (A) to produce the LLDPE, or vice versa, i.e. component (B) is produced first and then, in a subsequent polymerization step, component (A) is produced in the presence of component (B) to produce the LLDPE.
[0050] LLDPE produced in a multistage process is also known as an "in-situ" blend or a "reactor" blend. The resulting final product consists of an intimate mixture of polymers from two or more reactors whose different molecular weight distribution curves together form a molecular weight distribution curve with a broad maximum or two or more maxima, i.e., the final product is a multimodal polymer mixture.
[0051] In the context of a multimodal polyethylene, 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. The multimodal polyethylene may further have multimodality with respect to one or more other properties between the ethylene polymer components (A) and (B) and between the fractions (A-1) and (A-2), as described below.
[0052] The multimodal linear low density polyethylene (mLLDPE) of the present invention as defined above, below or in the claims is herein also referred to as "mLLDPE" for short.
[0053] The ethylene polymer component (A) and the ethylene polymer component (B), when both are mentioned, are also referred to as "ethylene polymer components (A) and (B)".
[0054] The following preferred embodiments, properties and subgroups of mLLDPE and its ethylene polymer components (A) and (B), and optionally its ethylene polymer parts (A-1) and (A-2), and the films 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 mLLDPE and articles of the present invention.
[0055] For the purpose of this specification and the subsequent claims, the term "polyethylene recovery blend (PCR)" is defined as the presence of at least two different polyethylenes, such as two high density polyethylenes of different densities. For example, bimodal polyethylene obtained from two reactors operating under different conditions constitutes a polyethylene blend, in this case an in situ blend of the two reactor products.
[0056] It goes without saying that polyethylene blends obtained from consumer waste will include a variety of polyethylenes. In addition to being contaminated with other plastics (mainly polypropylene, polystyrene, polyamide, polyester), wood, paper, limonene, aldehydes, ketones, fatty acids, metals and / or stabilizer long-term decomposition products may also be found. It goes without saying that such contamination is undesirable.
[0057] It should be understood that the polyethylene recycled blend of the present invention is not a cookie-cutter blend like some commercially available recyclables.The polyethylene recycled blend according to the present invention should be different from the virgin blend.
[0058] The term "C2 moiety" refers to repeating -[C2H4]- units derived from ethylene, present in a linear backbone and short chain branches, as measured by quantitative 13C{1H} NMR spectroscopy, wherein the repeating means at least two units.
[0059] The C2 part can be calculated as follows
[0060] wtC2 portion = fCC2 total * 100 / (fCC2 total + fCPP)
[0061] in
[0062] fCC2 total = (Iddg - ItwoB4) + (IstarB1 * 6)+(IstarB2 * 7)+(ItwoB4 * 9)
[0063] +(IthreeB5 * 10)+((IstarB4plus-ItwoB4-IthreeB5) * 7)+(I3s * 3)
[0064] and
[0065] fCPP=Isαα * 3
[0066] Details are given in the experimental section.
[0067] Due to the presence of HDPE, LDPE or LLDPE, polyethylene homopolymers and polyethylene copolymers in the recycled blends, analytical separation becomes an essential means for characterization. An appropriate method is the chemical composition analysis by cross fractionation chromatography (CFC). This method has been described and successfully implemented by Polymer Char, Valencia Technology Par, Gustave Eiffel 8, Paterna E-46980 Valencia, Spain. The chemical composition analysis by cross fractionation chromatography (CFC) allows fractionation into a homopolymer fraction (HPF) and a copolymer fraction (CPF) and possible iso-PP (IPPF). The homopolymer fraction (HPF) is a fraction that includes polyethylene similar to homopolymer-HDPE. The copolymer fraction (CPF) is a fraction similar to polyethylene HDPE copolymers, but may also include LDPE (respectively LLDPE) fractions. The iso-PP fraction (IPPF) includes isotactic polypropylene and is defined as the polymer fraction eluting at temperatures of 104°C and above. The homopolymer fraction (HPF), the copolymer fraction (CPF) and any iso-PP fraction (IPPF) added up to 100 wt. %. It goes without saying that 100 wt. % refers to the material that is soluble in a cross fractionation chromatography (CFC) experiment.
[0068] In addition to the chemical composition analysis by cross fractionation chromatography (CFC), the polyethylene blend according to the invention is characterized in that the amount of C2 fraction measured by NMR of the d2-tetrachloroethylene soluble fraction is greater than 95.0 wt%, preferably greater than 97.0 wt%. The percentages refer to the d2 tetrachloroethylene soluble fraction used for the NMR experiment. The term "C2 fraction" is equal to the polymer fraction obtainable from ethylene monomer units, i.e. not obtained from propylene monomer units.
[0069] The upper limit of the "C2 fraction" is 100 wt%.
[0070] Composition
[0071] Based on the total weight of the composition, the composition of the present invention comprises:
[0072] (I) 1.0 to 49.0 wt%, preferably 20.0 to 48.0 wt%, more preferably 30.0 to 45.0 wt% of a metallocene-catalyzed multimodal linear low density polyethylene (mLLDPE), and
[0073] (II) 51.0 to 99.0 wt%, preferably 52.0 to 80.0 wt%, more preferably 55.0 to 70.0 wt% of a polyethylene recycled blend (PCR).
[0074] The amounts of (I) and (II) preferably add up to at most 100.0 wt%.
[0075] (I) Multimodal mLLDPE and ethylene polymer components (A) and (B) and ethylene polymer fractions (A-1) and (A-2)
[0076] The metallocene-catalyzed multimodal linear low density polyethylene (mLLDPE) is referred to herein as "multimodal" because the ethylene-1-butene polymer component (A) (optionally comprising ethylene polymer fractions (A-1) and (A-2)) and the ethylene-1-hexene polymer component (B) are produced under different polymerization conditions, resulting in different melt flow rates (MFR, e.g. MFR2). That is, the multimodal mLLDPE is multimodal at least with respect to the difference in MFR2 of the ethylene polymer components (A) and (B).
[0077] In one embodiment of the present invention, the ethylene-1-butene polymer component (A) is unimodal, i.e. consists of only one fraction. In another embodiment, the ethylene-1-butene copolymer (A) consists of ethylene polymer fractions (A-1) and (A-2).
[0078] As mentioned above, the MFR2 of the ethylene polymer components (A) and (B) are different from each other.
[0079] The MFR2 of the ethylene polymer component (A) is in the range of 1.0 to 100.0 g / 10 min, preferably 2.0 to 80.0 g / 10 min, more preferably 3.0 to 70.0 g / 10 min, even more preferably 4.0 to 60.0 g / 10 min.
[0080] The MFR2 of the ethylene polymer component (B) is in the range of 0.001 to 1.0 g / 10 min, preferably 0.002 to 0.8 g / 10 min, more preferably 0.003 to 0.6 g / 10 min, even more preferably 0.004 to 0.4 g / 10 min.
[0081] In case the ethylene-1-butene polymer component (A) consists of ethylene polymer fractions (A-1) and (A-2), the MFR2 of the ethylene polymer fractions (A-1) and (A-2) may be different from each other or may be the same.
[0082] The MFR2 of the ethylene polymer parts (A-1) and (A-2) is in the range of 0.1 to 150.0 g / 10min, preferably 1.0 to 120.0 g / 10min, more preferably 2.0 to 100.0 g / 10min, even more preferably 3.0 to 90.0 g / 10min, such as 5.0 to 85.0 g / 10min.
[0083] In one embodiment of the present invention the MFR2 of ethylene polymer fraction (A-2) is equal to or preferably higher than the MFR2 of ethylene polymer fraction (A-1).
[0084] Therefore, the ratio of MFR2 of fraction (A-2) to MFR2 of fraction (A-1), i.e. MFR2(A-2) / MFR2(A-1), is in the range of ≥1.0 to 150, preferably 1.5 to 100, more preferably 2.0 to 60.
[0085] The MFR2 of the multimodal mLLDPE is in the range of 0.1 to 2.0 g / 10 min, preferably 0.2 to 1.5 g / 10 min, more preferably 0.3 to 1.0 g / 10 min.
[0086] The MFR of the multimodal mLLDPE 21 (190° C., 21.6 kg, ISO 1133) is in the range of 5.0 to 75.0 g / 10 min, preferably 8.0 to 50.0 g / 10 min, more preferably 10.0 to 30.0 g / 10 min.
[0087] MFR of multimodal mLLDPE 21 The MFR / MFR2 ratio is in the range of 15.0 to 60.0, preferably 30.0 to 55.0, more preferably 40.0 to 50.0.
[0088] Of course, besides the multimodality with respect to (i.e. the difference between) the MFR2 of the ethylene polymer components (A) and (B), the multimodal mLLDPE of the invention may also be multimodal with respect to, for example, the density of the ethylene polymer components (A) and (B).
[0089] Preferably, the density of the ethylene polymer component (A) is different from, preferably higher than, the density of the ethylene polymer component (B).
[0090] The density of the ethylene polymer component (A) is 925 to 960 kg / m 3 , preferably 930 to 955 kg / m 3 , more preferably 932 to 952 kg / m 3 The density of the ethylene polymer component (B) is in the range of 880 to 915 kg / m 3 , preferably 890 to 905 kg / m 3 within the range.
[0091] The density of the polymer parts (A-1) and (A-2) is 925 to 960 kg / m 3 , preferably 928 to 958 kg / m 3 , more preferably 930 to 955 kg / m 3 , such as 935 to 952 kg / m 3 within the range.
[0092] The densities of the polymer parts (A-1) and (A-2) may be the same as or may be different from each other.
[0093] The density of multimodal mLLDPE is between 910 and 925 kg / m 3 , preferably 912 to 923 kg / m 3 , more preferably 914 to 922 kg / m 3 , even more preferably 915 to 921 kg / m 3 within the range.
[0094] More preferably, the multimodal mLLDPE is multimodal (i.e. there is a difference between them) at least with respect to MFR2, the comonomer types and the density of the ethylene polymer component mMDPE (respectively (A) and (B)) is multimodal (i.e. there is a difference between them), as defined above, below or in the claims, the claims including any preferred ranges or embodiments of the polymer composition.
[0095] Within the scope of the present invention, the first and second ethylene polymer parts (A-1 and A-2) of the ethylene polymer component (A) are present in a weight ratio of 4:1 to 1:4, such as 3:1 to 1:3, or 2:1 to 1:2, or 1:1.
[0096] The ethylene-1-butene polymer component (A) is present in an amount of 30.0 to 70.0 wt%, preferably in an amount of 32.0 to 55.0 wt%, even more preferably in an amount of 34.0 to 48.0 wt%, based on the multimodal mLLDPE.
[0097] Thus, the ethylene-1-hexene polymer component (B) is present in an amount of 70.0 to 30.0 wt%, preferably in an amount of 68.0 to 45.0 wt%, more preferably in an amount of 66.0 to 52.0 wt%, based on the multimodal mLLDPE.
[0098] The metallocene-catalyzed multimodal mLLDPE can be produced in a two-stage process, which preferably comprises a slurry reactor (loop reactor), wherein the slurry (loop) reactor is connected in series to a gas phase reactor (GPR), wherein ethylene polymer component (A) is produced in the loop reactor and ethylene polymer component (B) is produced in the GPR in the presence of ethylene polymer component (A) to produce the multimodal mLLDPE.
[0099] In case the ethylene component (A) of the multimodal mLLDPE consists of ethylene polymer fractions (A-1) and (A-2), the multimodal mLLDPE can be produced in a three-stage process, which preferably comprises a first slurry reactor (loop reactor 1), wherein the first slurry loop reactor is connected in series to a further slurry reactor (loop reactor 2) such that the first ethylene polymer fraction (A-1) produced in loop reactor 1 is fed to loop reactor 2, where the second ethylene polymer fraction (A-2) is produced in the presence of the first fraction (A-1). Hence, loop reactor 2 is connected in series to a gas phase reactor (GPR) such that the first ethylene polymer fraction (A) leaving the second slurry reactor is fed to the GPR to produce a trimodal mLLDPE. In this case, the reaction conditions in the two slurry reactors are selected such that products different in MFR and / or density are produced in the two slurry reactors.
[0100] Such processes are described inter alia in WO 2016 / 198273, WO 2021009189, WO 2021009190, WO 2021009191 and WO 2021009192. Full details on how to prepare suitable metallocene-catalyzed multimodal mLLDPE can be found in these references.
[0101] A suitable process is the Borstar PE process or the Borstar PE 3G process.
[0102] Therefore, the metallocene-catalyzed multimodal mLLDPE according to the present invention is preferably produced in a loop-loop-gas phase cascade. Such a polymerization step may be preceded by a prepolymerization step. The purpose of the prepolymerization is to polymerize a small amount of polymer onto the catalyst at low temperature and / or low monomer concentration. By prepolymerization, the performance of the catalyst in slurry can be improved and / or the properties of the final polymer can be modified. The prepolymerization step is preferably carried out in slurry and the amount of polymer produced in the optional prepolymerization step is counted as the amount (wt%) of ethylene polymer component (A).
[0103] When there is a prepolymerization step, the catalyst components are preferably all introduced into the prepolymerization step. However, when the solid catalyst component and the cocatalyst can be fed separately, it is possible that only a part of the cocatalyst is introduced into the prepolymerization stage, while the rest is introduced into the subsequent polymerization stage. Moreover, in this case, it is necessary to introduce so much cocatalyst into the prepolymerization stage in order to obtain a sufficient polymerization reaction therein.
[0104] It is to be understood that within the scope of the present invention the amount of polymer produced in the prepolymerisation is within 1 to 5 wt% relative to the final metallocene-catalysed multimodal mLLDPE. This may be counted as part of the first ethylene polymer component (A).
[0105] catalyst
[0106] The metallocene-catalyzed multimodal mLLDPE used in the method of the present invention is mLLDPE prepared using a metallocene catalyst. The metallocene catalyst comprises a metallocene complex and a cocatalyst. The metallocene compound or complex is also referred to herein as an organometallic compound (C).
[0107] The organometallic compound (C) comprises a transition metal (M) from Groups 3 to 10 of the Periodic Table of Elements (IUPAC 2007) or from the actinides or lanthanides.
[0108] According to the present invention, the term "organometallic compound (C)" includes any metallocene or non-metallocene compound of a transition metal, which carries at least one organic (coordinating) ligand and exhibits catalytic activity alone or together with a cocatalyst. Transition metal compounds are well known in the art, and the present invention encompasses compounds of metals from Groups 3 to 10, e.g. Groups 3 to 7, or Groups 3 to 6, e.g. Groups 4 to 6, of the Periodic Table (IUPAC 2007), as well as lanthanides or actinides.
[0109] In one embodiment, the organometallic compound (C) has the following formula (I):
[0110]
[0111] Wherein each X is independently a halogen atom, C 1-6 -alkyl, C 1-6 - alkoxy, phenyl or benzyl;
[0112] Each Het is independently a monocyclic heteroaromatic group containing at least one heteroatom selected from O or S;
[0113] L is -R'2Si-, wherein each R' is independently a C substituted with an alkoxy group having 1 to 10 carbon atoms. 1-20 -Hydrocarbon or C 1-10 -alkyl;
[0114] M is Ti, Zr or Hf;
[0115] Each R 1 Same or different, is C 1-6 -alkyl or C 1-6 - alkoxy;
[0116] Each n is 1 to 2;
[0117] Each R 2 Same or different, is C 1-6 -alkyl, C 1-6 -alkoxy or -Si(R)3 group;
[0118] Each R is optionally replaced by 1 to 3 C 1-6 -alkyl substituted C 1-10 - alkyl or phenyl; and
[0119] Each p is from 0 to 1.
[0120] Preferably, the compound of formula (I) has the following structure (I')
[0121]
[0122] Wherein each X is independently a halogen atom, C 1-6 -alkyl, C 1-6 -alkoxy, phenyl or benzyl; L is Me2Si-;
[0123] Each R 1 Same or different and C 1-6 - alkyl, for example methyl or tert-butyl;
[0124] Each n is 1 to 2;
[0125] R 2 is -Si(R)3alkyl; each p is 1;
[0126] Each R is C 1-6 -alkyl or phenyl.
[0127] Highly preferred complexes of formula (I) or (I') are
[0128]
[0129]
[0130] Most preferably, the complex dimethylsilanediylbis[2-(5-trimethylsilylfuran-2-yl)-4,5-dimethylcyclopentadien-1-yl]zirconium dichloride is used as the organometallic compound (C) of the following formula (I).
[0131] More preferably, the ethylene polymer components (A) and (B) of the multimodal mLLDPE are prepared using, ie in the presence of, the same metallocene catalyst.
[0132] To form the catalyst, a cocatalyst, also called an activator, well known in the art is used. Cocatalysts containing Al or B are well known and can be used here. Preferably, an aluminoxane (such as MAO) or a boron-based cocatalyst (such as a borate) is used.
[0133] The metallocene-catalyzed multimodal mLLDPE may contain other polymer components and optional additives and / or fillers. In case the metallocene-catalyzed multimodal mLLDPE contains other polymer components, the amount of the other polymer components typically varies between 3.0 and 20.0 wt%, based on the total amount of the metallocene-catalyzed multimodal mLLDPE and the other polymer components.
[0134] Optional additives and fillers and the amounts used are conventional in the field of film applications. Examples of such additives are, inter alia, antioxidants, processing stabilizers, UV stabilizers, pigments, fillers, antistatic additives, antiblocking agents, nucleating agents, acid scavengers and polymer processing aids (PPAs).
[0135] It is to be understood herein that any additives and / or fillers may optionally be added to a so-called masterbatch comprising the respective additive and a carrier polymer.
[0136] (II) Polyethylene recycled blend (PCR)
[0137] In addition to the metallocene-catalyzed multimodal mLLDPE, the composition of the invention also comprises a polyethylene recycled blend (PCR).
[0138] The melt flow rate MFR5 (ISO 1133, 5.0 kg; 190° C.) of the polyethylene recycling blend (PCR) according to the present invention is typically 0.1 to 10.0 g / 10 min. The melt flow rate may be affected by segmenting post-consumer plastic waste streams, for example but not limited to: originating from extended producer responsibility programs such as the German DSD, or sorting a large number of pre-sorted fractions from municipal solid waste and recombining them in an appropriate manner. Typically the MFR5 is in the range of 0.5 to 5.0 g / 10 min, preferably 0.7 to 4.0 g / 10 min, most preferably 1.0 to 3.0 g / 10 min.
[0139] The polyethylene recycled blend (PCR) according to the present invention has a C2 fraction higher than 95.0 wt%, preferably higher than 97.0 wt%, more preferably higher than 98.0 wt%, most preferably higher than 99.0 wt%, as measured by NMR of the d2-tetrachloroethylene soluble fraction.
[0140] Typically, recycling properties can be assessed by the presence of one or more of the following:
[0141] (1) an inorganic residue content higher than 0.01 wt% (measured by thermogravimetric analyzer); at the same time, 10 m 2 OCS gels with sizes ranging from 100 to 299 microns were measured in the range of 500 to 5000 counts / m2 for the membrane;
[0142] Alternatively or in combination
[0143] (2) limonene in an amount of 0.5 ppm or more as determined by using solid phase microextraction (HS-SPME-GC-MS);
[0144] Alternatively or in combination
[0145] (3) Fatty acids selected from the group consisting of acetic acid, butyric acid, valeric acid and hexanoic acid, the total amount of which is 10 ppm or more as measured by using solid phase microextraction (HS-SPME-GC-MS).
[0146] It will be appreciated that options (2) and (3) are preferred.
[0147] "Fatty acids selected from the group consisting of acetic acid, butyric acid, valeric acid and caproic acid" means that the individual amounts of acetic acid, butyric acid, valeric acid and caproic acid (determined in ppm by HS-SPME-GC-MS) are added together.
[0148] The detection limit of limonene in solid phase microextraction (HS-SPME-GC-MS) is below 0.1 ppm, which means that trace amounts of these substances can be easily determined and their recovery properties can be determined.
[0149] It goes without saying that the content of inorganic residues, gels, limonene and fatty acids should be as low as possible.
[0150] Particularly preferred is
[0151] Limonene is present in an amount of 0.1 to 25 ppm, even more preferably 0.1 to 20 ppm, as determined by using solid phase microextraction (HS-SPME-GC-MS); and / or the total amount of fatty acids consisting of the group of acetic acid, butyric acid, valeric acid and caproic acid is present in a total amount of at least 10 to 500 ppm, more preferably 10 to 300 ppm, most preferably 10 to 180 ppm, as determined by using solid phase microextraction (HS-SPME-GC-MS).
[0152] With regard to color, two embodiments can be distinguished: an essentially colorless blend and an essentially white blend.
[0153] CIELAB color space (L * a * b * )for
[0154] L * 75.0 to 86.0;
[0155] a * -5.0 to 0.0;
[0156] b * 5.0 to less than 25.0
[0157] CIELAB color space (L * a * b * )for
[0158] L * Above 86.0 to 97.0;
[0159] a * -5.0 to 0.0;
[0160] b * 0.0 to less than 5.0.
[0161] The polyethylene recycled blend (PCR) according to the invention is preferably characterized by an odor (VDA270-B3) of 2.5 or less, preferably 2.0 or less. It should be understood that many commercial recycled grades that do not report an odor are actually even unacceptable in this respect, since the sniff test proposed by VDA270 is prohibited due to the presence of problematic or toxic substances.
[0162] The polyethylene recycled blend (PCR) according to the present invention has one or more of the following OCS gel count properties (for 10 m 2 Membrane measurement):
[0163] Size 300 to 599 microns: 100 to 2500 counts / m²
[0164] Size 600 to 1000 microns: 5 to 200 counts / m²
[0165] Size greater than 1000 microns: 1 to 40 counts / m²
[0166] OCS gels are given in counts / m2, calculated as 10m 2 The average value of the membrane.
[0167] In another aspect, the polyethylene recycled blend (PCR) according to the present invention has a tensile modulus (ISO 527-2, crosshead speed 1 mm / min; 23° C.) of at least 825 MPa, preferably at least 850 MPa, most preferably at least 910 MPa, measured using injection molded specimens as described in EN ISO 1873-2 (dog bone shape, 4 mm thickness). Typically the tensile modulus will not be higher than 1100 MPa.
[0168] It is also preferred that the polyethylene recycled blend (PCR) has no units derived from isotactic polypropylene when subjected to NMR analysis as described in the specification.
[0169] In another preferred aspect, the polyethylene recycled blend (PCR) according to the present invention has a LAOS-NLF 1000% (190°C) of 2.1 to 2.9, preferably 2.2 to 2.7, most preferably 2.3 to 2.6. LAOS-NLF 1000% is a rheological measure of the long chain branching content, defined as
[0170]
[0171] in
[0172] G1' is the first order Fourier coefficient
[0173] G3' is the third-order Fourier coefficient
[0174] A medium or low value of 1000% for LAOS-NLF indicates very low, i.e. practically negligible, amounts of LDPE or LLDPE. LAOS-NLF further indicates a nonlinear polymer structure. In addition to sorting LDPE and LLDPE, LAOS-NLF can also be influenced by blending several recycling streams from different sources (e.g. different states) (after determining the value).
[0175] The polyethylene recycled blend (PCR) according to the present invention preferably has a shear thinning factor (STF) higher than 46.0, more preferably between 48.0 and 60.0.
[0176]
[0177] The shear thinning factor (STF) indicates the processability of polyethylene. The shear thinning factor (STF) can also be influenced by mixing predetermined material flows.
[0178] On the other hand, the polyethylene blend according to the present invention preferably has a polydispersity index (PI) higher than 2.0, more preferably from 2.1 to 2.7,
[0179]
[0180] Wherein Gc is the crossover modulus, which is the value of the shear storage modulus G' when the shear storage modulus G' is equal to the shear loss modulus G". The polydispersity index (PI) is a rheological measure of the breadth of the molecular weight distribution. From the perspective of processability, especially moldability, higher values, for example above 2.0 or in the range of 2.1 to 2.7 are preferred.
[0181] The polyethylene recycled blend according to the present invention is preferably in the form of pellets. Pelletization helps to reduce the content of volatile matter and also helps homogenization.
[0182] The Charpy notched impact strength of the polyethylene recycled blend according to the present invention is preferably higher than 35.0 kJ / m at 23°C. 2 , more preferably above 45 kJ / m at 23°C 2 At -20°C, the Charpy notched impact strength of the polyethylene blend according to the present invention is preferably higher than 18.0 kJ / m at 23°C. 2 , more preferably higher than 22 kJ / m 2 .
[0183] The yield tensile stress is preferably higher than 25.0 MPa.
[0184] The method for providing the polyethylene recycling blend according to the present invention is very demanding. The method comprises the following steps:
[0185] i) providing post-consumer plastic waste, preferably high purity polyethylene from individual waste collection or municipal solid waste collection;
[0186] ii) Sorting out items made of polystyrene, polyamide, polypropylene, metal, paper and wood, thus providing post-consumer plastic materials;
[0187] iii) sorting out colored items, thereby providing a post-consumer plastic material mainly comprising white bottles, white yogurt cups, white jars, colorless panels, colorless parts, etc., and steps ii) and iii) can be combined or performed separately;
[0188] iv) optionally sorting out impurities by manual inspection.
[0189] receiving two streams of polyethylene material therefrom, a first stream being substantially transparent and a second stream being substantially white;
[0190] v) grinding the two streams separately, washing in aqueous solutions containing various detergents, and then drying, exhausting and screening to obtain two pretreated streams;
[0191] vi) further sorting the two pretreated streams (both; separately) to remove non-polyolefin and color fractions;
[0192] vii) extruding into small pellets;
[0193] viii) optional aeration, which is preferably carried out at a temperature in the range of 100-130°C by preheating the post-consumer plastic to this temperature using an air stream having a temperature of at least 100°C for at least 20 hours.
[0194] Aeration is usually necessary but can be skipped in specific circumstances.
[0195] Odor control and assessment can be achieved by a variety of methods. Demets, Ruben et al. provide a review, "Development and application of an analytical method to quantify odour removal in plastic waste recycling processes." Resources, Conservation and Recycling 161 (2020): 104907, which is incorporated herein by reference.
[0196] If necessary, inorganic residues can be reduced by solution technology. OCS gel counting parameters can be controlled to avoid contaminants, such as pigments from colored materials, etc. Manual sorting is preferably assisted by NIR spectroscopy, which is also easily available in the form of small portable equipment. This allows the polypropylene content to be suppressed to a minimum. The density can be affected by reducing the amount of relatively flexible polyethylene products. The relative amount of the homopolymer part (HPF) and the copolymer part (CPF) can be controlled by wind conversion (this machine is also called a wind screen), which uses air flow to separate the material into different streams according to the size, shape and especially weight of the particles. For example, polyethylene films (i.e. LLDPE / LDPE with a relatively high copolymer fraction (CPF)) can be eliminated. CIELAB is controlled by a combination of color sorting and elimination of non-polyethylene polymer impurities.
[0197] The film of the present invention
[0198] The film of the present invention comprises at least one layer comprising a composition as described above. The film may be a monolayer film comprising the composition or a multilayer film, wherein at least one layer comprises the composition. The terms "monolayer film" and "multilayer film" have well-known meanings in the art.
[0199] The monolayer film or the layers of the multilayer film of the present invention may consist of the composition of the present invention itself or of a blend of said composition with other polymers. In the case of a blend, any other polymer is different from the metallocene-catalyzed multimodal mLLDPE and is preferably a polyolefin. Some of the above-mentioned additives, such as processing aids, may optionally be added to the metallocene-catalyzed multimodal mLLDPE during the film preparation process.
[0200] 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%, yet more preferably at least 80 wt% of the composition of the present invention.Most preferably, said at least one layer of the film of the present invention consists of the composition.
[0201] Thus, the films of the invention may comprise a single layer (ie a monolayer) or may be multilayer.Multilayer films typically and preferably comprise at least 3 layers.
[0202] 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 film or cast film, especially a blown film. For example, blown film is produced by extruding through an annular die and blowing into a tubular film by forming bubbles, which burst between rollers after solidification. The film can then be cut, cut or converted (e.g., folded) as required. Traditional film production techniques can be used in this regard. If preferred blown film or cast film is a multilayer film, each layer is typically coextruded. The technician will know suitable extrusion conditions.
[0203] The film according to the present invention may be subjected to post-treatment processes such as surface modification, lamination or orientation processes, etc. Such orientation processes may be uniaxial (MDO) or biaxial orientation, wherein uniaxial orientation is preferred.
[0204] In another preferred embodiment, the film is non-oriented.
[0205] The resulting film can have any thickness conventional in the art. The thickness of the film is not important and depends on the end use. Therefore, the film can have, for example, 300 μm or less, typically 6 to 200 μm, preferably 10 to 180 μm, for example 20 to 150 μm or 20 to 120 μm. If desired, the polymer of the present invention can achieve a thickness of less than 100 μm, for example less than 50 μm. It is also possible to produce a film of the present invention with a thickness even less than 20 μm while maintaining good mechanical properties.
[0206] Furthermore, the present invention also relates to the use of the inventive preparation as packaging material, in particular as packaging material for secondary packaging, which does not require food approval or even non-food primary packaging.
[0207] The films of the invention are characterized by a dart drop impact strength (DDI) of at least 80 g to at most 500 g, preferably 90 g to at most 300 g, more preferably 100 g to at most 150 g, measured according to ISO 7765-1:1988, method A on a 40 μm single layer test blown film.
[0208] The films according to the invention have good stiffness (tensile modulus measured on 40 μm monolayer test blown films according to ISO 527-3), ie >420 MPa (in both directions).
[0209] Thus, the tensile modulus of films comprising the composition of the present invention (measured according to ISO 527-3 on a 40 μm monolayer test blown film) is in the range of >420 MPa to 900 MPa, preferably 450 MPa to 850 MPa, more preferably 480 MPa to 800 MPa in the machine direction (MD) and in the range of >520 MPa to 1200 MPa, preferably 550 MPa to 1150 MPa, more preferably 680 MPa to 1100 MPa in the transverse direction (TD).
[0210] The present invention will be further described with reference to the following non-limiting examples.
[0211] Determination method
[0212] Unless otherwise stated in the description or in the experimental section, the following methods were used to determine the properties of the polymers (including parts and components thereof) and / or any sample preparations thereof as described in the text or in the experimental section.
[0213] Melt flow rate:
[0214] The melt flow rate (MFR) is determined according to ISO 1133 and is expressed in g / 10 min. The MFR of polyethylene is determined at 190°C. The MFR can be determined at different loads, such as 2.16 kg (MFR2), 5 kg (MFR5) or 21.6 kg (MFR 21 ).
[0215] Calculation of MFR2 of component B and part (A-2)
[0216] logA=x·logB+(1-x)·logC
[0217]
[0218] For component B:
[0219] B = MFR2 of component (A)
[0220] C = MFR2 of component (B)
[0221] A = Final MFR2 of multimodal medium density polyethylene (mMDPE) (blend)
[0222] X = weight fraction of component (A)
[0223] For part (A-2):
[0224] B = MFR2 of the first part (A-1)
[0225] C = MFR2 of the second part (A-2)
[0226] A = Final MFR2 of cyclic polymer (= component (A)) (mixture)
[0227] X = weight fraction of the first part (A-1)
[0228] density
[0229] The density of polymers is measured according to ISO 1183 and is expressed in kg / m 3 Given, sample preparation was performed according to ISO 1872-2.
[0230] C2 moiety determined by NMR spectroscopy and general microstructure including “continuous C3” and short chain branches
[0231] A Bruker AVNEO 400 MHz NMR spectrometer was used to analyze the 1 H and 13 C was operated at 400.15 and 100.62 MHz and quantitative data were recorded in solution. 13 C{ 1 H}NMR spectra. All spectra were obtained using 13 C optimized 10 mm extended temperature probe was recorded at 125 °C, and nitrogen was used for all pneumatics. Approximately 200 mg of material was dissolved in approximately 3 mg of 1,2-tetrachloroethane-d2 (TCE-d2) together with approximately 3 mg of BHT (2,6-di-tert-butyl-4-methylphenol CAS 128-37-0) and chromium (III) acetylacetonate (Cr(acac)3) to obtain a 60 mM solution of the relaxation agent in the solvent {singh09}. To ensure a homogeneous solution, the NMR tube was further heated in a rotary oven for at least 1 hour after initial preparation of the sample in a heat block. The tube was rotated at a frequency of 10 Hz during insertion into the magnet. Standard single pulse excitation without NOE was used, using an optimized tip angle, a recycle delay of 1 s, and a dual-level WALTZ16 decoupling scheme {zhou07, busico07}. A total of 6144 (6k) transients were acquired for each spectrum.
[0232] Quantitative 13 C{ 1 The H} NMR spectra were processed, integrated, and the relevant quantitative properties were determined from the integration using a proprietary computer program. All chemical shifts were indirectly referenced to the central methylene of the ethylene block (EEE) at 30.00 ppm using the chemical shift of the solvent. Characteristic signals corresponding to polyethylene and polypropylene with different short chain branches (B1, B2, B4, B5, B6plus) were observed {randall89, brandolini00}.
[0233] Characteristic signals corresponding to the presence of polyethylene were observed, and the polyethylene contained isolated B1 branches (starB1 33.3ppm), isolated B2 branches (starB2 39.8ppm), isolated B4 branches (twoB4 23.4ppm), isolated B5 branches (threeB5 32.8ppm), all branches longer than 4 carbons (starB4plus 38.3ppm) and the third carbon from the end of the saturated aliphatic chain (3s 32.2ppm). If one or another structural element is not observed, it is excluded from the equation. The combined intensity of the ethylene backbone methine carbon (dd 30.0ppm), γ-carbon (g 29.6ppm), 4s and threeB4 carbon (compensated later) is between 30.9ppm and 29.3ppm, excluding Tββ from polypropylene. The amount of C2 related carbon is quantified using all mentioned signals according to the following equation:
[0234] f C2总计 =(Iddg-ItwoB4)+(IstarB1 * 6)+(IstarB2 * 7)+(ItwoB4 * 9)
[0235] +(IthreeB5 * 10)+((IstarB4plus-ItwoB4-IthreeB5) * 7)+(I3s * 3)
[0236] While characteristic signals corresponding to the presence of polypropylene (PP, continuous C3) were observed at 46.7 ppm, 29.0 ppm, and 22.0 ppm, the amount of PP-related carbon was quantified using the Sαα integral at 46.6 ppm:
[0237] f PP =Isαα * 3
[0238] The weight percentage of C2 fraction and polypropylene can be quantified according to the following equation:
[0239] wt C2部分 =fC C2总计 * 100 / (fC C2总计 +fC PP )
[0240] wt PP =fC PP * 100 / (fC C2总计 +fCPP )
[0241] Characteristic signals corresponding to the various short chain branches are observed and quantified as their weight percentage of the relevant branch will be the alpha olefin, first quantifying the weight fraction of each:
[0242] fwtC2=fC C2总计 -(IstarB1 * 3)-(IstarB2 * 4)-(ItwoB4 * 6)-(IthreeB5 * 7)
[0243] fwtC3 (separation C3) = IstarB1 * 3
[0244] fwtC4=IstarB2 * 4
[0245] fwtC6=ItwoB4 * 6
[0246] fwtC7=IthreeB5 * 7
[0247] Normalization of all weight fractions results in the quantity of weight percentages of all relevant branches:
[0248] fsum wt%总计 =fwtC2+fwtC3+fwtC4+fwtC6+fwtC7+fC PP
[0249] wtC2 total = fwtC2*100 / fsum wt%总计
[0250] wtC3 total = fwtC3*100 / fsum wt%总计
[0251] wtC4 total = fwtC4*100 / fsum wt%总计
[0252] wtC6 total = fwtC6*100 / fsum wt%总计
[0253] wtC7 total = fwtC7*100 / fsum wt%总计
[0254] zhou07
[0255] Zhou,Z.,Kuemmerle,R.,Qiu,X.,Redwine,D.,Cong,R.,Taha,A.,Baugh,D.Winniford,B.,J.Mag.Reson.187(2007)225
[0256] busico07
[0257] Busico,V.,Carbonniere,P.,Cipullo,R.,Pellecchia,R.,Severn,J.,Talarico,G.,Macromol.Rapid Commun.2007,28,1128
[0258] singh09
[0259] Singh,G.,Kothari,A.,Gupta,V.,Polymer Testing 28 5(2009),475
[0260] randall89
[0261] J. Randall, Macromol. Sci., Rev. Macromol. Chem. Phys. 1989, C29, 201.
[0262] brandolini00
[0263] AJBrandolini,DDHills,NMR Spectra of Polymers and PolymerAdditives,
[0264] Marcel Dekker Inc., 2000
[0265] Polymer composition analysis by CFC - determination of homopolymer fraction (HPF), copolymer fraction (CPF) and iso-PP fraction (IPPF)
[0266] The chemical composition distribution at a certain elution temperature (polymer crystallinity in solution) as well as the determination of the molecular weight distribution and the corresponding molecular weight averages (Mn, Mw and Mv) were determined by fully automated cross-fractionation chromatography (CFC) as described in Ortin A., Monrabal B., Sancho-Tello J., Macromol. Symp., 2007, 257, 13-28.
[0267] Cross-fractionation chromatography (TREF xSEC) was performed using a CFC instrument (PolymerChar, Valencia, Spain). The concentration was monitored using a quad band IR5 infrared detector (PolymerChar, Valencia, Spain). The polymer was dissolved at 160°C for 180 minutes at a concentration of approximately 0.4 mg / ml.
[0268] To avoid injection of gels and polymers that are not soluble in TCB at 160°C, such as PET and PA, the weighed samples were loaded into a stainless steel mesh MW 0077 / D 0,05 mmm.
[0269] After the sample was completely dissolved, a 0.5 ml aliquot was loaded into the TREF column and stabilized at 110 °C for 60 min. A temperature of 60 °C was reached by applying a constant cooling rate of 0.07 °C / min to allow the polymer to crystallize and precipitate. The following temperature steps were used for the discontinuous elution process: (60, 65, 69, 73, 76, 79, 80, 82, 85, 87, 89, 90, 91, 92, 93, 94, 95, 95, 96, 97, 98, 99, 100, 102, 104, 107, 120, 130)
[0270] In the second dimension, GPC analysis used 3PL Olexis columns and 1x Olexis Guard columns from Agilent (Church Stretton, UK) as stationary phases. 1,2,4-Trichlorobenzene (TCB, stabilized with 250 mg / L 2,6-di-tert-butyl-4-methylphenol) was applied as eluent at a constant flow rate of 1 mL / min at 150°C. The column set was calibrated using universal calibration (according to ISO 16014-2:2003) with at least 15 narrow MWD polystyrene (PS) standards ranging from 0.5 kg / mol to 11500 kg / mol. The following Mark Houwink constants were used to convert PS molecular weights to PE molecular weight equivalents.
[0271] K PS =19x 10 -3 mL / g, α PS =0.655
[0272] K PE =39x 10 -3 mL / g, α PP =0.725
[0273] A third order polynomial fit was used to fit the calibration data. Data processing was performed using software provided by PolymerChar and the CFC instrument.
[0274] Calculation of the homopolymer fraction (HPF), copolymer fraction (CPF) and iso-PP fraction (IPPF).
[0275] The definitions of the homopolymer fraction (HPF), copolymer fraction (CPF) and iso-PP fraction (IPPF) are as follows:
[0276] 100% = CPF + HPF + IPPF
[0277] The IPPF fraction is defined as the polymer fraction eluting at temperatures of 104°C and above.
[0278] Due to the slight dependence of the TREF curve on the low MW portion, the molecular weight limit of the low MW limit depends on the elution temperature (T el ). Use the following formula to determine the low MW limit:
[0279] Lower MW limit (for HPF part) = 0.0125 * T el +2.875
[0280] Taking this into account, the HPF fraction was calculated using the following method.
[0281]
[0282] Among them, H ij The corresponding elution temperature (Tel)i and logM
[0283] 2D differential distribution for value j.
[0284] Inorganic residues
[0285] The inorganic residues were determined by TGA using a TGA Discovery TGA5500 according to DIN ISO 11358-1:2014. Approximately 10-30 mg of material were placed in a platinum pan. The sample was heated under nitrogen at a heating rate of 20°C / min. At 850°C, the ash content was evaluated in wt%.
[0286] OCS Gel
[0287] Cast film samples with a thickness of about 70 μm were extruded and inspected using a CCD (charge coupled device) camera, image processor and evaluation software (instrument: OCS-FSA100, supplier OCS GmbH (Optical Control Systems)). Film defects were measured and classified according to their circle diameter. 2 The films were analyzed and the values per square meter were calculated as average values.
[0288] Cast film preparation, extrusion parameters:
[0289] 1. Output 25±4g / min
[0290] 2. Extruder temperature curve: 200-210-210-200 (melting temperature 224°C)
[0291] 3. Film thickness is about 70μm
[0292] 4. Cooling roller temperature 80℃
[0293] 5. Airknife 6400NI / h (volume)
[0294] Technical data of extruder:
[0295] 1. Screw type: 3-zone, nitrification
[0296] 2. Screw diameter: 25mm
[0297] 3. Screw length: 25D
[0298] 4. Feeding area: 10D
[0299] 5. Compression area: 4D + output area 11D
[0300] 6. Mould 150mm
[0301] According to size (μm) / m 2 Classify defects:
[0302] 100-299μm
[0303] 300-599μm
[0304] 600-999μm
[0305] 1000μm and above
[0306] CIELAB color space (L * a * b * )
[0307] In CIE L * a * b * In uniform color space, measured according to DIN EN ISO 11664-4, the color coordinates are: L * —brightness coordinate; a * —Red / Green coordinate, +a * Indicates red, -a * Indicates green; b * —Yellow / blue coordinate, +b * Indicates yellow, -b *Indicates blue. * 、a * and b * The coordinate axes define the three-dimensional CIE color space. Standard Konica / MinoltaColorimeter CM-3700A.
[0308] Assessing recyclable properties
[0309] Limonene content
[0310] Quantification of limonene was performed as described in the experimental part of EP 3757152.
[0311] Fatty acid detection
[0312] Fatty acid quantification was performed using headspace solid phase microextraction (HS-SPME-GC-MS) by standard addition.
[0313] 50 mg of ground sample was weighed in a 20 mL headspace vial, and after adding different concentrations of limonene and a glass-coated magnetic stirring bar, the vial was closed with a magnetic cap lined with silicone / PTFE. A 10 μL microcapillary was used to add known concentrations of a diluted free fatty acid mixture (acetic acid, propionic acid, butyric acid, valeric acid and caproic acid, optionally octanoic acid) standard to the sample at three different levels. 0, 50, 100 and 500 ng were added to equal 0 mg / kg, 1 mg / kg, 2 mg / kg and 10 mg / kg of each acid. For quantification, ion 60 obtained in SIM mode was used for all acids except propionic acid, where ion 74 was used.
[0314] GCMS parameters:
[0315] Column: 20m ZB Wax plus 0.25 * 0.25
[0316] Syringe: Split 5:1, Split liner with glass liner, 250℃
[0317] Temperature program: 40℃(1min)@6℃ / min to 120℃, @15℃ to 245℃(5min)Carrier: Helium 5.0, Linear speed 40cm / s, Constant current
[0318] MS: Single quadrupole, direct interface, 220°C interface temperature
[0319] Acquisition: SIM scan mode
[0320] Scan parameters: 46-250amu 6.6 scans / second
[0321] SIM parameters: m / z 60, 74, 6.6 scans / sec.
[0322] Metal
[0323] Determined by X-ray fluorescence (XRF).
[0324] Benzene content
[0325] By HS GC-MS 80℃ / 2h, described as follows
[0326] Static Headspace Analysis
[0327] The parameters for the static headspace gas chromatography-mass spectrometry (HS / GC / MS) method are presented here.
[0328] Weigh 4.000 ± 0.100 g of sample in a 20 ml sealed vial and seal tightly with a PTFE cap.
[0329] The mass spectrometer was operated in scan mode and a total ion chromatogram (TIC) was recorded for each analysis. Further details on applicable method parameters and data evaluation are as follows:
[0330] -HS parameters (Agilent G1888 Headspace Sampler)
[0331]
[0332] Low jitter
[0333] -GC parameters (Agilent 7890A GC system)
[0334] Column: ZB-WAX 7HG-G007-22 (30m x 250μm x 1μm)
[0335] Carrier gas: Helium 5.0
[0336] Flow rate: 2ml / min
[0337] Split: 5:1
[0338] GC oven program: 35°C for 0.1 min
[0339] 10℃ / min up to 250℃
[0340] 250℃ for 1min
[0341] -MS parameters (Agilent 5975C inert XL MSD)
[0342] Acquisition Mode: Scan
[0343] Scan parameters:
[0344] Low Quality: 20
[0345] High quality: 200
[0346] Threshold: 10
[0347] - Software / data evaluation
[0348] MSD ChemStation E.02.02.1431
[0349] MassHunter GC / MS Acquisition B.07.05.2479
[0350] AMDIS GC / MS Analytical Version 2.71
[0351] NIST Mass Spectral Library Version 2.0g
[0352] - AMDIS deconvolution parameters
[0353]
[0354] Data evaluation
[0355] The TIC data is further deconvolved with the help of AMDIS software (see the above parameters) and compared with a custom target library based on the mass spectral library (NIST). In the custom target library, the respective mass spectra of selected substances (such as benzene) are included. A substance is only accepted as "preliminary identification" when the identified peak shows a minimum match factor of 80 and is confirmed by an experienced mass spectrometrist.
[0356] In this study, the statement "below the detection limit (<LOD)" refers to the case where the match factor is below 80 (AMDIS) or the peak itself cannot even be identified. The results only refer to the measured samples, measurement time, and applied parameters.
[0357] Odor VDA270 - B3
[0358] VDA 270 is the determination of the odor characteristics of motor vehicle trim materials. The odor is determined according to VDA 270 (2018) variant B3. After lifting the can lid as little as possible, each assessor evaluates the odor of the individual samples according to the VDA 270 scale. The six-level (hexamerous scale) consists of the following grades: Grade 1: Not noticeable, Grade 2: Noticeable, not disturbing, Grade 3: Clearly noticeable, but not disturbing, Grade 4: Disturbing, Grade 5: Strongly disturbing, Grade 6: Unacceptable. The assessors remain calm during the assessment and are not allowed to bias each other by discussing individual results during the test. They are also not allowed to adjust their assessment after testing another sample. For statistical reasons (as accepted by VDA 270), the assessors are forced to use the full step in the assessment. Therefore, the odor grade is based on the average of all individual assessments and is rounded to a whole number.
[0359] Rheological measurements
[0360] Dynamic shear measurement (frequency sweep measurement)
[0361] Characterization of polymer compositions or melts of polymers by dynamic shear measurements as described above or below, in accordance with ISO standards 6721-1 and 6721-10. Measurements were performed on an Anton Paar MCR501 stress-controlled rotational rheometer equipped with 25 mm parallel plate geometry. Measurements were performed on compression molded plaques using a nitrogen atmosphere and setting the strain in the linear viscoelastic range. Oscillatory shear tests were performed at 190°C, using a frequency range between 0.01 and 600 rad / s, with a gap setting of 1.3 mm.
[0362] Further details are described in the experimental part, paragraph i) of EP 3757152.
[0363] The shear thinning factor (STF) is defined as
[0364]
[0365] These values were determined by means of a single-point interpolation procedure defined in the Rheoplus software. In cases where a given G* value was not reached experimentally, it was determined by extrapolation using the same procedure as before. Also in this case (interpolation or extrapolation), the options "Interpolate y-values of parameter to x-values" and "Logarithmic interpolation type" in Rheoplus were applied (see above).
[0366] Large Amplitude Oscillatory Shear (LAOS)
[0367] The nonlinear viscoelastic behavior under shear flow is investigated using large amplitude oscillatory shear. The method requires the application of a sinusoidal strain amplitude of 0 at a given angular frequency for a given time t. If the applied sinusoidal strain is high enough, a nonlinear response will result. In this case, the stress is a function of the applied strain amplitude, time, and angular frequency. Under these conditions, the nonlinear stress response is still a periodic function; however, it can no longer be expressed by a single harmonic sinusoid. The stress [0-0] resulting from the nonlinear viscoelastic response can be represented by a Fourier series that includes higher harmonic contributions:
[0368] σ(t,ω,γ0)=γ0.∑ n [G′ n (ω,γ0).sin(nωt)+G″ n (ω,γ0).cos(nωt)] (1)
[0369] Where, σ-stress response
[0370] t-time
[0371] ω-Frequency
[0372] γ0-strain amplitude
[0373] n - number of harmonics
[0374] G′ n -Order elastic Fourier coefficient
[0375] G″ n -order viscosity Fourier coefficient
[0376] The nonlinear viscoelastic response was analyzed using large amplitude oscillatory shear (LAOS). Time sweep measurements were performed on an Alpha Technologies RPA2000 rheometer in combination with a standard double cone die. During the measurements, the test chamber was sealed and a pressure of approximately 6 MPa was applied. LAOS tests were performed at an applied temperature of 190°C, an angular frequency of 0.628 rad / s and a strain of 1000%. To ensure that steady-state conditions were achieved, the nonlinear response was determined only after at least 20 cycles were completed for each measurement. The large amplitude oscillatory shear nonlinear factor (LAOS_NLF) is defined as follows:
[0377]
[0378] Where G′1-first order Fourier coefficient
[0379] G′3 - third-order Fourier coefficient
[0380] [1] J.M. Dealy, K.F. Wissbrun, Melt Rheology and Its Role in Plastics Processing: Theory and Applications; edited by Van Nostrand Reinhold, New York (1990)
[0381] [2] S. Filipe, Non-Linear Rheology of Polymer Melts, AIP Conference Proceedings 1152, pp. 168 - 174 (2009)
[0382] [3] M. Wilhelm, Macromol. Mat. Eng. 287, 83 - 105 (2002)
[0383] [4] S. Filipe, K. Hofstadler, K. Klimke, A.T. Tran, Non-Linear Rheological Parameters for Characterisation of Molecular Structural Properties in Polyolefins, Proceedings of Annual European Rheology Conference, 135 (2010)
[0384] [5] S. Filipe, K. Klimke, A.T. Tran, J. Reussner, Proceedings of Novel Non-Linear Rheological Parameters for Molecular Structural Characterisation of Polyolefins, Novel Trends in Rheology IV, Zlin, Check Republik (2011)
[0385] [6] K.Klimke, S.Filipe, ATTran, Non-linear rheological parameters for characterization of molecular structural properties in polyolefins, Proceedings of European Polymer Conference, Granada, Spain (2011)
[0386] Dart Drop Intensity (DDI)
[0387] DDI was measured according to ISO 7765-1:1988 / Method A on films (non-oriented films and laminates) produced as shown below. This test method covers the determination of the energy that will cause film failure under specified conditions of impact with a dart falling freely from a specified height, which will cause 50% of the test specimens to fail (Step Method A). A uniform increment of the missile mass was used during the test, and after each specimen test, the missile weight was reduced or increased by a uniform increment depending on the observed result (failure or no failure) of the specimen.
[0388] Standard conditions:
[0389] Adjustment time: >96h at 50±2℃±10%rh
[0390] Test temperature: 23℃
[0391] Dart head material: phenolic resin
[0392] Dart diameter: 38mm
[0393] Drop height: 660mm
[0394] Result: Impact failure weight -50% [g]
[0395] Tensile modulus
[0396] Tensile modulus (E-Mod (MPa)) according to ISO 527-3,
[0397] On a film sample with a thickness of 40 μm prepared as described in Film Sample Preparation,
[0398] The measurements were made in the machine / transverse direction with a cross head speed of 1 mm / min of modulus.
[0399] Membrane sample preparation
[0400] A Collin 30 laboratory scale monolayer blown film line was used to prepare test films with a thickness of 40 μm consisting of the composition of the present invention and the respective comparative compositions. The film samples were produced at 194° C., a blow ratio of 1:2.5, and a frost line distance of 120 mm.
[0401] Experimental Section
[0402] I) mLLDPE
[0403] Cat. Example: Preparation of Catalyst of Example IE1 of the Present Invention
[0404] SiO2 loading:
[0405] 10 kg of silica (PQ Corporation ES757, calcined at 600°C) was added from a feed bucket and inerted in the reactor until the O2 level reached less than 2 ppm.
[0406] Preparation of MAO / tol / MC:
[0407] At 25°C (oil circulation temperature) and 95rpm stirring, a 30wt% MAO toluene solution (14.1kg) was added from a balance to another reactor, followed by toluene (4.0kg). After adding toluene, the stirring speed was increased from 95rpm to>200rpm, with a stirring time of 30 minutes. Metallocene racemic-dimethylsilanediylbis{2-(5-(trimethylsilyl)furan-2-yl)-4,5-dimethylcyclopentadiene-1-yl}zirconium dichloride 477g was added from a metal cylinder, followed by 4kg toluene rinse (total toluene was 8.0kg). The reactor stirring speed was changed to 95rpm for MC feeding, returned to 200rpm and continued for 3h reaction time. After the reaction time, the MAO / tol / MC solution was transferred to a feed container.
[0408] Preparation of catalyst:
[0409] The reactor temperature was set to 10°C (oil circulation temperature) and stirring was adjusted to 40 rpm during the addition of MAO / tol / MC. MAO / tol / MC solution (22.2 kg) was added over 205 min, followed by a stirring time of 60 min (oil circulation temperature set to 25°C). After stirring, the "dry mix" 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 a speed of 5 rpm.
[0410] After stabilization, the catalyst was dried at 60°C (oil circulation temperature) for 2 h under a 2 kg / h nitrogen flow, followed by drying under vacuum for 13 h (same nitrogen flow rate, stirring at 5 rpm). The dried catalyst was sampled and the HC content was measured using a Sartorius moisture analyzer (model MA45) in a glove box using thermogravimetry. The target HC level was <2% (actual 1.3%).
[0411] Polymerization: Inventive Example: Multimodal mLLDPE of ethylene with 1-butene and 1-hexene comonomers for IE
[0412] The Borstar pilot plant had a three-reactor set-up (Loop 1 - Loop 2 - GPR1) and a prepolymerization loop reactor.
[0413] The polymerisation conditions given in Table 1 were used to produce a multimodal mLLDPE according to the invention (mLLDPE-1).
[0414] Table 1: Polymerization conditions
[0415]
[0416]
[0417] The polymer was mixed with 2400 ppm of Irganox B561 (supplied by BASF) and 270 ppm of Dynamar FX 5922 (supplied by 3M), compounded and extruded into pellets using a JSW extruder under a nitrogen atmosphere so that SEI was 230 kWh / kg and the melt temperature was 250°C.
[0418] Table 2: Material properties of multimodal mLLDPE-1
[0419]
[0420] II) Polyethylene recycled blend (PCR)
[0421] Multiple post-consumer plastic waste HDPE streams from a separate plastic waste collection (a municipal facility providing specific HDPE collection) were roughly sorted based on polymer properties and color. Impurities were further separated by manual inspection. Two streams were received, namely a stream of a colorless fraction and a stream of a white fraction. The colorless fraction stream (separately) was ground, washed in an aqueous solution with various detergents, then dried and screened to obtain a pretreated stream. The pretreated stream was further sorted to reduce the colored fraction and non-polyolefins. After preheating the matrix particles to at least 100°C, the particles were extruded into pellets and aerated in air at 120°C for 22 hours. A substantially colorless PCR was obtained. Table 3 shows the results for the final material.
[0422] All examples were subjected to polymer composition analysis by CFC.
[0423] Table 3: Characteristics of colorless PCR
[0424]
[0425]
[0426] Multimodal mLLDPE was blended with polyethylene recycled blend (PCR) and converted into blown films.
[0427] For CE1, ExxonMobile’s Enable 3505CH was used: a metallocene-catalyzed medium-density ethylene-1-hexene copolymer; density 935 kg / m 3 , MFR2 0.5g / 10min
[0428] For CE2, Total was used Supertough 40ST05: metallocene polyethylene; density 940kg / m 3 , MFR2 0.5g / 10min.
[0429] For CE3, a Ziegler-Natta catalyzed HDPE and another recyclate, NAV101, a low-density polyethylene (LDPE) post-consumer recyclate blend available from Ecoplast Kunststoffrecycling GmbH was used:
[0430] CAT2 of Comparative Example 3
[0431] For Comparative Example 3, the ZN catalyst disclosed in EP2994506 was used.
[0432] Polymerization of Comparative Example 3
[0433] The Borstar pilot plant had a two-reactor unit (loop 1 - GPR 1) and a prepolymerization reactor.
[0434] The polymerization conditions given in Table 4 were used to produce ZN-HDPE.
[0435] Table 4: Polymerization conditions of ZN-HDPE
[0436]
[0437] The polymer was mixed with 0.05 wt% Irganox 1010 (BASF), 0.2 wt% Irgafos 168 (BASF) and 0.05 wt% CEASIT FI (Baerlocher) calcium stearate, wherein the wt% is relative to the total weight of the composition (the sum of HDPE powder + additives = 100%), compounded and extruded on a ZSK 57 twin-screw extruder. The melt temperature was 210° C. and the production rate was 200 kg / h.
[0438] Table 5: Material properties of ZN-HDPE
[0439] Material HDPE-2 <![CDATA[MFR2 (g / 10 min) (Final)]]> 0.80 <![CDATA[MFR 21 (g / 10min)]]> 47.35 <![CDATA[MFR 21 / MFR2]]> 59.2 <![CDATA[Density (kg / m 3 )]]> 956
[0440] Table 6: Properties of NAV 101
[0441] Ethylene content (wt%) 90.67 <![CDATA[Density (kg / m 3 )]]> 923.9 <![CDATA[MFR2(g / 10min)]]> 1.02 <![CDATA[MFR5(g / 10min)]]> 3.57 <![CDATA[MFR 21 (g / 10min)]]> 41.56
[0442] Table 7: Blend and film properties
[0443]
[0444] As can be clearly seen from the above table, the membrane of inventive example IE1 consisting of the composition of the present invention has very similar mechanical properties compared to the original materials of the prior art such as Enable and Supertough.
[0445] If different blends are used, such as r-LDPE (NAV101) and virgin HDPE of CE3, the resulting films have poorer stiffness and impact resistance compared to IE1.
Claims
1. A composition comprising: (I) 1.0 to 49.0 wt% of a metallocene-catalyzed linear low-density polyethylene (mLLDPE), based on the total weight of the composition, wherein the metallocene-catalyzed linear low-density polyethylene (mLLDPE) consists of (i) 30.0 to 70.0 wt% of an ethylene-1-butene polymer component (A) based on the total weight of mLLDPE and (ii) 70.0 to 30.0 wt% of an ethylene-1-hexene polymer component (B) based on the total weight of the mLLDPE, wherein the ethylene-1-butene polymer component (A) has ·925 to 960 kg / m 3 Density in the range of 1.0 to 2.0 g / 10 min (ISO 1183) and MFR2 in the range of 1.0 to 100.0 g / 10 min (190°C, 2.16 kg, ISO 1133); The ethylene-1-hexene polymer component (B) has 880 to 915 kg / m 3 range (ISO 1183) and MFR2 (190°C, 2.16kg, ISO 1133) in the range of 0.001 to 1.0 g / 10 min; and mLLDPE has ·910 to 925 kg / m 3 Density in the range (ISO 1183), MFR2 (190°C, 2.16 kg, ISO 1133) in the range of 0.1 to 2.0 g / 10 min, and MFR in the range of 5.0 to 75.0 g / 10 min 21 (190°C, 21.6kg, ISO 1133), and MFR in the range of 15.0 to 60.0 21 / MFR2 ratio; and (II) 51.0 to 99.0 wt% of a polyethylene recycled blend (PCR), based on the total weight of the composition, having (i) MFR5 (ISO 1133, 5.0 kg; 190° C.) of 0.1 to 10 g / 10 min, and (ii) 950 to 970 kg / m 3 The density of (iii) a C2 fraction in an amount greater than 95.0 wt% as measured by NMR of the d2-tetrachloroethylene soluble fraction, and (iv) a PCR-based homopolymer fraction (HPF) content in the range of 80.0 to 91.0 wt % as determined by chemical composition analysis by cross fractionation chromatography (CFC), and (v) a PCR-based copolymer fraction (CPF) content in the range of 9.0 to 20.0 wt% as determined by chemical composition analysis by cross fractionation chromatography (CFC), and (vi) optionally a PCR-based iso-PP fraction (IPPF) content in the range of 0.0 to 2.0 wt% as determined according to chemical composition analysis by cross fractionation chromatography (CFC), wherein the iso-PP fraction (IPPF) is defined as the polymer fraction eluting at a temperature of 104°C and above, wherein the homopolymer fraction (HPF), the copolymer fraction (CPF) and the iso-PP fraction (IPPF) add up to 100 wt%, and (vii) 0.01 to 2.00 wt% inorganic residue (measured by TGA) relative to the total polyethylene recycled blend, and (viii) 10m by OCS counting instrument 2 OCS gels having a size of 100 to 299 microns measured in the range of 500 to 5000 counts / square meter; wherein (ix) CIELAB color space (L * a * b * ) is -L * 75.0 to 86.0; -a * -5.0 to 0.0; -b * 5.0 to less than 25.0 or (x) CIELAB color space (L * a * b * ) is -L * Above 86.0 to 97.0; -a * -5.0 to 0.0; -b * 0.0 to less than 5.
0.
2. The composition of claim 1, wherein in the metallocene-catalyzed multimodal linear low density polyethylene (mLLDPE), 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), The density (ISO 1183) of parts (A-1) and (A-2) is between 925 and 960 kg / m 3 and MFR2 (190°C, 2.16 kg, ISO 1133) is in the range of 0.1 to 150.0 g / 10 min, and wherein the densities of ethylene polymer fractions (A-1) and (A-2) may be the same or may be different and the MFR2 (190°C, 2.16 kg, ISO 1133) of the ethylene polymer fraction (A-2) is equal to, preferably higher than, the MFR2 of the ethylene polymer fraction (A-1).
3. The composition of claim 1 or 2, wherein in the metallocene-catalyzed multimodal linear low density polyethylene (mLLDPE), the MFR2 of the ethylene polymer component (A) is in the range of 2.0 to 80.0 g / 10 min, preferably 3.0 to 70.0 g / 10 min, more preferably 4.0 to 60.0 g / 10 min, and / or The MFR2 of the ethylene polymer component (B) is in the range of 0.002 to 0.8 g / 10 min, preferably 0.003 to 0.6 g / 10 min, even more preferably 0.004 to 0.4 g / 10 min.
4. The composition according to claim 2 or 3, wherein in the metallocene-catalyzed multimodal linear low density polyethylene (mLLDPE), the ratio of MFR2 of fraction (A-2) to MFR2 of fraction (A-1) MFR2(A-2) / MFR2(A-1) is in the range of ≥1.0 to 150, preferably 1.5 to 100, more preferably 2.0 to 60.
5. The composition according to any one of the preceding claims, wherein the metallocene-catalyzed multimodal linear low density polyethylene (mLLDPE) has an MFR2 in the range of 0.2 to 1.5 g / 10 min, preferably 0.3 to 1.0 g / 10 min.
6. The composition according to any one of the preceding claims, wherein in the metallocene-catalyzed multimodal linear low density polyethylene (mLLDPE) The density (ISO 1183) of the ethylene polymer component (A) is between 930 and 955 kg / m 3 , more preferably 932 to 952 kg / m 3 Within the range, The density (ISO 1183) of the ethylene polymer component (B) is between 890 and 905 kg / m 3 within the range, and Density (ISO 1183) of the metallocene-catalyzed multimodal linear low density polyethylene (mLLDPE) 912 to 923 kg / m 3 , preferably 914 to 922 kg / m 3 , more preferably 915 to 921 kg / m 3 within the range.
7. The composition according to any one of the preceding claims, wherein the polyethylene recycled blend (PCR) Have one or both of the following characteristics: a) limonene content determined by using solid phase microextraction (HS-SPME-GC-MS) in an amount of 0.1 to 25 ppm, preferably 0.1 to 20 ppm b) a total amount of fatty acids consisting of the group of acetic acid, butyric acid, valeric acid and caproic acid of 10 to 500 ppm, preferably 10 to 300 ppm, determined by using solid phase microextraction (HS-SPME-GC-MS).
8. The composition according to any one of the preceding claims, wherein the polyethylene recycled blend (PCR) has an odor (VDA 270-B3) of 2.5 or less, preferably 2.0 or less.
9. The composition of any one of the preceding claims, wherein the polyethylene recycled blend (PCR) has one or more of the following OCS gel count properties: a) OCS gel with a size of 300 to 599 microns: 100 to 2500 counts / m2; b) OCS gel with a size of 600 to 1000 microns: 10 to 200 counts / m2; c) OCS gels with a size greater than 1000 μm: 1 to 40 counts / m2; All of these are counted by OCS instruments for 10m 2 The measurements were performed as described in the experimental section.
10. The composition according to any one of the preceding claims, wherein the polyethylene recycled blend (PCR) has a tensile modulus of at least 825 MPa, preferably at least 850 MPa, most preferably at least 910 MPa to 1100 MPa using injection molded specimens as described in EN ISO 1873-2 (dog bone shape, 4 mm thickness) (ISO 527-2, crosshead speed of 1 mm / min; 23°C).
11. The composition according to any one of the preceding claims, wherein the Large Amplitude Oscillatory Shear-Non-Linear Factor (LAOS-NLF) of the Polyethylene Recycled Blend (PCR) (190°C; 1000%) in G1' is the first order Fourier coefficient G3' is the third-order Fourier coefficient In the range of 2.1 to 2.9, preferably 2.2 to 2.7, most preferably 2.3 to 2.
6.
12. The composition according to any one of the preceding claims, wherein the shear thinning factor (STF) of the polyethylene recycling blend (PCR) is It is higher than 46.0, preferably 48.0 to 60.
0.
13. A film comprising the composition according to any one of the preceding claims 1 to 12.
14. The film according to claim 13, wherein the film is characterized by a dart drop impact strength (DDI) determined according to ISO 7765-1:1988, method A on a 40 μm monolayer test blown film of at least 80 g and up to 500 g, preferably 90 g to 300 g, more preferably 100 g to 150 g, and a tensile modulus (measured according to ISO 527-3 on a 40 μm monolayer test blown film) in the machine direction (MD) in the range of >420 MPa to 900 MPa, preferably 450 MPa to 850 MPa, more preferably 480 MPa to 800 MPa and in the transverse direction (TD) in the range of >520 MPa to 1200 MPa, preferably 550 MPa to 1150 MPa, more preferably 680 to 1100 MPa.
15. Use of a film according to any of the preceding claims 13 to 14 as packaging material, in particular for secondary packaging not requiring food approval or even for primary packaging of non-food products.
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