Polyolefin composition for films having an excellent balance of stiffness and toughness

Abstract

The present invention relates to compositions comprising a polyethylene-based material and a polypropylene-based material and to methods of forming films therefrom and films formed thereby.

Description

TECHNICAL FIELD

[0001] The present invention relates to a composition comprising a polyethylene-based material and a polypropylene-based material and a method of forming a film therefrom and a film formed therefrom. BACKGROUND

[0002] In producing polymer films, particularly cast films, it is desirable to have a polymer with good processability to achieve commercial production rates while maintaining sufficient toughness. In addition, physical properties required for the final film product include stiffness, toughness, and / or tear strength, among others.

[0003] Stiffness and toughness are key properties for polyethylene (PE) films. Examples of applications in which stiffness and toughness of PE films are key properties include stand-up pouches, sealed pouches, heavy duty sacks, and the like. Toughness can be characterized, for example, by dart drop resistance and puncture strength. Stiffness can be characterized, for example, by machine direction (MD) 1% secant modulus.

[0004] High density polyethylene (HDPE) and polypropylene (PP) are two possible blending partners for polyethylene (PE) films to improve stiffness. However, there are limited cases where PP is chosen as a blending partner because PP and PE have different crystalline phases and types, and there is little or no co-crystallization between PP and PE. It is generally believed by those skilled in the art that blending PP with PE can improve the stiffness of PE films, but will simultaneously decrease the toughness of PE films.

[0005] On the other hand, PP has many advantages over HDPE, such as lower density, higher stiffness, and higher heat resistance. If PP can be used in most PE formulations to improve the stiffness of films and still maintain the toughness performance, it would show great value to the industry and food packaging thickness reduction for PP / PE film structures.

[0006] Accordingly, there is a need for improved polyolefin compositions having improved stiffness and having an excellent balance of stiffness and toughness, and methods of forming films from the polyolefin compositions and films formed from the polyolefin compositions.

[0007] Related publications include, for example, WO 2017 / 068106 and WO 2021 / 040760. SUMMARY

[0008] The present invention provides polyolefin compositions using PP instead of HDPE, and methods of forming films from the polyolefin compositions and films formed from the polyolefin compositions, wherein the polyolefin compositions of the present invention using PP unexpectedly achieve an excellent balance of stiffness and toughness compared to polyolefin compositions using HDPE.

[0009] According to one aspect of the present application, the present application provides a polyolefin composition comprising one or more broad orthogonal composition distribution (BOCD) polyethylenes and one or more polypropylenes.

[0010] According to embodiments of the present application, the polyolefin composition comprises (or consists essentially of, or consists of) from about 60 wt% to about 95 wt% of the BOCD polyethylene and from about 5 wt% to about 40 wt% of the polypropylene, based on the weight of the polyolefin composition.

[0011] According to embodiments of the present application, the polyolefin composition comprises, for example, from about 60 wt%, about 65 wt%, about 70 wt%, about 75 wt%, about 80 wt%, about 85 wt%, about 90 wt%, about 95 wt% of the BOCD polyethylene, based on the weight of the polyolefin composition. The range of the content of the BOCD polyethylene, based on the weight of the polyolefin composition, includes combinations of any two of the above content values, for example, from about 60 wt% to about 95 wt%, from about 60 wt% to about 90 wt%, and the like.

[0012] According to embodiments of the present application, the polyolefin composition comprises, for example, from about 5 wt%, about 10 wt%, about 15 wt%, about 20 wt%, about 25 wt%, about 30 wt%, about 35 wt%, about 40 wt% of the polypropylene, based on the weight of the polyolefin composition. The range of the content of the polypropylene, based on the weight of the polyolefin composition, includes combinations of any two of the above content values, for example, from about 5 wt% to about 40 wt%, from about 5 wt% to about 35 wt%, and the like.

[0013] According to embodiments of the present application, the BOCD polyethylene contains from about 70 mol% to about 99 mol% of polymer units derived from ethylene, based on the total number of moles of polymer units of the BOCD polyethylene, and has a density of from about 0.91 g / cm 3 to about 0.925 g / cm 3 , measured according to ASTM D-792 or ASTM D-1505, and a melt index (MI, or I 2.16 ), measured according to ASTM D-1238-E (190°C / 2.16 kg), of from about 0.5 g / 10 min to about 3.0 g / 10 min, preferably from about 1.0 g / 10 min to about 2.0 g / 10 min.

[0014] According to embodiments of the present application, the BOCD polyethylene is characterized by having a composition distribution breadth index (CDBI) of from about 25 wt% to about 55 wt%.

[0015] According to embodiments of the present application, the polypropylene is selected from the group consisting of homopolymers of polypropylene and impact copolymers of polypropylene, and combinations thereof.

[0016] According to embodiments of the present application, the homopolymer of polypropylene has a melt index from about 1 g / 10 min to about 6 g / 10 min, as determined according to ASTM D1238-L (230°C / 2.16 kg).

[0017] According to embodiments of the present application, the homopolymer of polypropylene has a density from about 0.8 g / cm 3 to about 0.98 g / cm 3 as determined according to ASTM D792-13.

[0018] According to embodiments of the present application, the homopolymer of polypropylene has a tensile strength at yield from about 20 MPa to about 100 MPa, as determined according to ASTM D638.

[0019] According to embodiments of the present application, the impact copolymer of polypropylene has a melt index from about 1 g / 10 min to about 6 g / 10 min, as determined according to ASTM D1238-L (230°C / 2.16 kg).

[0020] According to embodiments of the present application, the impact copolymer of polypropylene has a density from about 0.8 g / cm 3 to about 0.98 g / cm 3 as determined according to ASTM D792-13.

[0021] According to embodiments of the present application, the impact copolymer of polypropylene has a tensile strength at yield from about 10 MPa to about 100 MPa, as determined according to ASTM D638.

[0022] According to embodiments of the present application, the polyolefin composition of the present application has a machine direction (MD) 1% secant modulus from greater than about 200 MPa, preferably greater than about 250 MPa, preferably greater than about 300 MPa, preferably greater than about 350 MPa, preferably greater than about 400 MPa, to less than about 410 MPa, or less than about 400 MPa, or less than about 350 MPa, or less than about 300 MPa, or less than about 250 MPa, when a film comprising (or consisting essentially of, or consisting of) the polyolefin composition of the present application has a thickness of about 25 pm, wherein the machine direction (MD) 1% secant modulus is measured according to ASTM D 882 method.

[0023] According to embodiments of the present application, the polyolefin composition comprising polypropylene (PP) of the present application has substantially the same, preferably from greater than about 10%, or greater than about 20%, or greater than about 30%, or greater than about 40%, or greater than about 50%, or greater than about 60%, or greater than about 70%, or greater than about 80%, or greater than about 90%, or greater than about 100%, or greater than about 110%, or greater than about 120%, or greater than about 130%, or greater than about 140%, or greater than about 150%, or greater than about 160%, or greater than about 170%, or greater than about 180%, or greater than about 190%, or greater than about 200%, or greater than about 210%, or greater than about 220%, or greater than about 230%, or greater than about 240%, or greater than about 250%, to less than about 260%, or less than about 250%, or less than about 240%, or less than about 230%, or less than about 220%, or less than about 210%, or less than about 200%, or less than about 190%, or less than about 180%, or less than about 170%, or less than about 160%, or less than about 150%, or less than about 140%, or less than about 130%, or less than about 120%, or less than about 110%, or less than about 100%, or less than about 90%, or less than about 80%, or less than about 70%, or less than about 60%, or less than about 50%, of the dart impact strength / thickness value (g / μm), wherein the dart impact strength is measured according to ASTM D 1709 method, compared to a polyolefin composition that is identical except that high density polyethylene (HDPE) is used in place of polypropylene, wherein the high density polyethylene (HDPE) has a density greater than 0.940 g / cm 3 and a melt index from about 0.5 g / 10 min to about 10 g / 10 min, wherein the density is measured according to ASTM D-1505 and the melt index is measured according to ASTM D1238-E (190°C / 2.16 kg).

[0024] According to embodiments of the present application, the expression "substantially the same dart impact strength / thickness value (g / μm)" in relation to the polyolefin composition means that the dart impact strength / thickness value differs by about ± 1%, or differs by about ± 2%, or differs by about ± 3%, or differs by about ± 4%.

[0025] According to embodiments of the present application, the polyolefin composition comprising polypropylene (PP) of the present application has substantially the same, preferably from greater than about 4%, or greater than about 5%, or greater than about 6%, or greater than about 7%, or greater than about 8%, or greater than about 9%, or greater than about 10%, or greater than about 15%, or greater than about 20%, or greater than about 25%, or greater than about 26%, or greater than about 27%, or greater than about 28%, or greater than about 29%, to less than about 30%, or less than about 29%, or less than about 28%, or less than about 27%, or less than about 26%, or less than about 25%, or less than about 20%, or less than about 15%, or less than about 10%, or less than about 9%, or less than about 8%, or less than about 7% of the needle penetration strength value (mN / pm), wherein the needle penetration strength is measured according to CEN 14477 method, than a polyolefin composition that is otherwise identical except that high density polyethylene is used in place of the polypropylene, wherein the high density polyethylene (HDPE) has a density greater than 0.940 g / cm 3 of the melt index measured according to ASTM D-1238-E (190°C / 2.16 kg), and the BOCD polyethylene has a composition distribution breadth index (CDBI) of about 38.6 wt% or

[0026] According to embodiments of the present application, the expression "substantially the same needle penetration strength value (mN / pm)" with respect to the polyolefin composition means that the needle penetration strength values differ by about ±1%, or differ by about ±2%, or differ by about ±3%.

[0027] According to embodiments of the present application, the present application provides a polyolefin composition comprising from about 60 wt% to about 95 wt% of a BOCD polyethylene and from about 5 wt% to about 40 wt% of a polypropylene, based on the weight of the polyolefin composition,

[0028] wherein the BOCD polyethylene contains from about 70 mol% to about 99 mol% of polymer units derived from ethylene, based on the total number of moles of polymer units of the BOCD polyethylene, and has a density of about 0.918 g / cm 3 as measured according to ASTM D-792, and a melt index (MI, or I 2.16 ) of about 1.0 g / 10 min, as measured according to ASTM D-1238-E (190°C / 2.16 kg), and the BOCD polyethylene has a composition distribution breadth index (CDBI) of about 38.6 wt% or

[0029] wherein the BOCD polyethylene contains from about 70 mol% to about 99 mol% of polymer units derived from ethylene, based on the total number of moles of polymer units of the BOCD polyethylene, and has a density of about 0.915 g / cm3 a melt index (MI, or I 2.16 ), measured according to ASTM D-1238-E (190°C / 2.16 kg), and a BOCD polyethylene having a composition distribution breadth index (CDBI) of about 43 wt%,

[0030] wherein the polypropylene is selected from the group consisting of a homopolymer of polypropylene and an impact copolymer of polypropylene, and combinations thereof,

[0031] wherein the homopolymer of polypropylene has a melt index of about 3.2 g / 10 min, as determined according to ASTM D1238-L (230°C / 2.16 kg), and

[0032] wherein the impact copolymer of polypropylene has a melt index of about 4.0 g / 10 min, as determined according to ASTM D1238-L (230°C / 2.16 kg); or

[0033] Preferably, the homopolymer of polypropylene has a tensile strength at yield of about 31.5 MPa, as determined according to ASTM D638; or

[0034] Preferably, the impact copolymer of polypropylene has a density of 0.900 g / cm 3 Preferably, the impact copolymer of polypropylene has a tensile strength at yield of 23.7 MPa, as determined according to ASTM D638; or

[0035] Preferably, the polyolefin composition has a machine direction (MD) 1% secant modulus of from greater than about 200 MPa to less than about 410 MPa, as measured when a film comprising the polyolefin composition has a thickness of about 25 pm, wherein the machine direction (MD) 1% secant modulus is measured according to ASTM D 882 method; or

[0036] Preferably, the polyolefin composition comprising the polypropylene has a substantially same, or from greater than about 10% to less than about 260% dart drop impact strength / thickness value (g / pm) compared to a polyolefin composition identical in all respects except that the polypropylene is replaced with a high density polyethylene, wherein the dart drop impact strength is measured according to ASTM D 1709 method, wherein the high density polyethylene (HDPE) has a density of about 0.961 g / cm 3 Preferably, the polyolefin composition has a melt index of about 0.70 g / 10 min, as measured according to ASTM D1238-E (190°C / 2.16 kg); or

[0037] Preferably, the polyolefin composition comprising polypropylene has substantially the same, or a needle penetration value from greater than about 4% to less than about 30% (mN / pm), wherein the needle penetration is measured according to CEN 14477 method, compared to a polyolefin composition identical in all other respects except that high density polyethylene is used in place of polypropylene, wherein the high density polyethylene (HDPE) has a density of about 0.961 g / cm 3 and a melt index of about 0.70 g / 10 min, wherein the density is measured according to ASTM D-1505 and the melt index is measured according to ASTM D1238-E (190°C / 2.16 kg).

[0038] According to one aspect of the present application, the present application provides a film comprising (or consisting essentially of, or consisting of) the polyolefin composition of the present application.

[0039] The film of the present application can be a single layer film, or a multi-layer film, wherein any layer of the multi-layer film can comprise (or consist essentially of, or consist of) the polyolefin composition of the present application.

[0040] The film of the present application can be selected and determined in thickness as per the actual need.

[0041] The film of the present application can be manufactured using a casting method known in the art for manufacturing polyethylene (PE) film.

[0042] According to an embodiment of the present application, the film of the present application comprising (or consisting essentially of, or consisting of) the polyolefin composition has a machine direction (MD) 1% secant modulus from greater than about 200 MPa, preferably greater than about 250 MPa, preferably greater than about 300 MPa, preferably greater than about 350 MPa, preferably greater than about 400 MPa, to less than about 410 MPa, or less than about 400 MPa, or less than about 350 MPa, or less than about 300 MPa, or less than about 250 MPa, when the film comprising the polyolefin composition of the present application has a thickness of about 25 pm, wherein the machine direction (MD) 1% secant modulus is measured according to ASTM D 882 method.

[0043] According to embodiments of the present application, the film of the present application comprising (or consisting essentially of, or consisting of) a polyolefin composition has substantially the same, preferably from greater than about 10%, or greater than about 20%, or greater than about 30%, or greater than about 40%, or greater than about 50%, or greater than about 60%, or greater than about 70%, or greater than about 80%, or greater than about 90%, or greater than about 100%, or greater than about 110%, or greater than about 120%, or greater than about 130%, or greater than about 140%, or greater than about 150%, or greater than about 160%, or greater than about 170%, or greater than about 180%, or greater than about 190%, or greater than about 200%, or greater than about 210%, or greater than about 220%, or greater than about 230%, or greater than about 240%, or greater than about 250%, to less than about 260%, or less than about 250%, or less than about 240%, or less than about 230%, or less than about 220%, or less than about 210%, or less than about 200%, or less than about 190%, or less than about 180%, or less than about 170%, or less than about 160%, or less than about 150%, or less than about 140%, or less than about 130%, or less than about 120%, or less than about 110%, or less than about 100%, or less than about 90%, or less than about 80%, or less than about 70%, or less than about 60%, or less than about 50%, Dart Impact Strength / Thickness value (g / μm), wherein the Dart Impact Strength is measured according to ASTM D 1709 method, compared to a film that is otherwise identical except that high density polyethylene (HDPE) is used in place of polypropylene, wherein the high density polyethylene (HDPE) has a density greater than 0.940 g / cm 3 and a melt index from about 0.5 g / 10 min to about 10 g / 10 min, wherein the density is measured according to ASTM D-1505 and the melt index is measured according to ASTM D1238-E (190°C / 2.16 kg).

[0044] According to embodiments of the present application, the expression "substantially the same Dart Impact Strength / Thickness value (g / μm)" in reference to the film of the present application comprising (or consisting essentially of, or consisting of) a polyolefin composition means that the Dart Impact Strength / Thickness value differs by about ± 1%, or differs by about ± 2%, or differs by about ± 3%, or differs by about ± 4%.

[0045] According to embodiments of the present application, the film of the present application comprising (or consisting essentially of, or consisting of) a polyolefin composition has substantially the same, preferably from greater than about 4%, or greater than about 5%, or greater than about 6%, or greater than about 7%, or greater than about 8%, or greater than about 9%, or greater than about 10%, or greater than about 15%, or greater than about 20%, or greater than about 25%, or greater than about 26%, or greater than about 27%, or greater than about 28%, or greater than about 29%, to less than about 30%, or less than about 29%, or less than about 28%, or less than about 27%, or less than about 26%, or less than about 25%, or less than about 20%, or less than about 15%, or less than about 10%, or less than about 9%, or less than about 8%, or less than about 7% of the needle puncture strength value (mN / pm), wherein the needle puncture strength is measured according to CEN 14477 method, than a film that is otherwise identical except that high density polyethylene (HDPE) is used in place of the polypropylene, wherein the high density polyethylene (HDPE) has a density greater than 0.940 g / cm 3 and a melt index of about 0.5 g / 10 min to about 10 g / 10 min, wherein the density is measured according to ASTM D-1505 and the melt index is measured according to ASTM D1238-E (190 °C / 2.16 kg).

[0046] According to embodiments of the present application, the expression "substantially the same needle puncture strength value (mN / pm)" in reference to the film of the present application comprising (or consisting essentially of, or consisting of) a polyolefin composition means that the needle puncture strength values differ by about ± 1%, or differ by about ± 2%, or differ by about ± 3%.

[0047] According to embodiments of the present application, the present application provides a film comprising a polyolefin composition, wherein the polyolefin composition comprises about 60 wt% to about 95 wt% of a BOCD polyethylene and about 5 wt% to about 40 wt% of a polypropylene, based on the weight of the polyolefin composition,

[0048] wherein the BOCD polyethylene contains about 70 mol% to about 99 mol% of polymer units derived from ethylene, based on the total number of moles of polymer units of the BOCD polyethylene, and has a density of about 0.918 g / cm 3 as measured according to ASTM D-792, and a melt index (MI, or I 2.16 ) of about 1.0 g / 10 min, as measured according to ASTM D-1238-E (190 °C / 2.16 kg), and the BOCD polyethylene has a composition distribution breadth index (CDBI) of about 38.6 wt%, or

[0049] wherein the BOCD polyethylene has from about 70 mol% to about 99 mol% of polymer units derived from ethylene, based on the total number of moles of polymer units of the BOCD polyethylene, and a density of about 0.915 g / cm 3 as measured according to ASTM D1505, and a melt index (MI, or I 2.16 ) of about 1.4 g / 10 min, as measured according to ASTM D-1238-E (190°C / 2.16 kg), and the BOCD polyethylene has a composition distribution breadth index (CDBI) of about 43 wt%,

[0050] wherein the polypropylene is selected from the group consisting of a homopolymer of polypropylene and an impact copolymer of polypropylene, and combinations thereof,

[0051] wherein the homopolymer of polypropylene has a melt index of about 3.2 g / 10 min, as determined according to ASTM D1238-L (230°C / 2.16 kg), and

[0052] wherein the impact copolymer of polypropylene has a melt index of about 4.0 g / 10 min, as determined according to ASTM D1238-L (230°C / 2.16 kg); and

[0053] wherein the film has a machine direction (MD) 1% secant modulus of from greater than about 200 MPa to less than about 410 MPa, as measured when the film comprising the polyolefin composition has a thickness of about 25 pm, wherein the machine direction (MD) 1% secant modulus is measured according to ASTM D 882 method; or

[0054] Preferably, the homopolymer of polypropylene has a density of about 0.900 g / cm 3 as determined according to ASTM D792-13; preferably, the homopolymer of polypropylene has a tensile strength at yield of about 31.5 MPa, as determined according to ASTM D638; or

[0055] Preferably, the impact copolymer of polypropylene has a density of 0.900 g / cm 3 as determined according to ASTM D792-13; preferably, the impact copolymer of polypropylene has a tensile strength at yield of 23.7 MPa, as determined according to ASTM D638; or

[0056] Preferably, wherein the film comprising the polypropylene has substantially the same, or from greater than about 10% to less than about 260% of the dart drop impact strength / thickness value (g / pm) compared to a film that is identical in all other respects except that the polypropylene is replaced with a high density polyethylene (HDPE), wherein the high density polyethylene (HDPE) has a density of about 0.961 g / cm 3a density of about 0.96 g / cm3and a melt index of about 0.70 g / 10 min, where the density is measured according to ASTM D-1505 and the melt index is measured according to ASTM D1238-E (190°C / 2.16 kg); or

[0057] Preferably, the film comprising polypropylene has substantially the same, or a needle penetration strength value (mN / pm) from greater than about 4% to less than about 30% compared to a film identical in all other respects except that the polypropylene is replaced with high density polyethylene, where the needle penetration strength is measured according to CEN 14477 method, where the high density polyethylene (HDPE) has a density of about 0.961 g / cm3and a melt index of about 0.70 g / 10 min, where the density is measured according to ASTM D-1505 and the melt index is measured according to ASTM D1238-E (190°C / 2.16 kg). 3 a density of about 0.96 g / cm3and a melt index of about 0.70 g / 10 min, where the density is measured according to ASTM D-1505 and the melt index is measured according to ASTM D1238-E (190°C / 2.16 kg).

[0058] According to one aspect of the present application, the present application provides a package, such as an industrial package and a food package, comprising the film of the present application, wherein the film of the present application comprises the polyolefin composition of the present application.

[0059] According to embodiments of the present application, the film manufactured according to the present application is suitable for use in a stand-up, flexible package or pouch. Such a package would be stiff enough to form a shape that would enable it to stand up, for example, with a label on its front face, but flexible enough to allow a user to bend and / or squeeze the package, thereby forcing and / or pouring out a liquid.

[0060] Broad Orthogonal Composition Distribution (BOCD) Polyethylene

[0061] The polyolefin composition of the present application comprises one or more broad orthogonal composition distribution (BOCD) polyethylenes. The broad orthogonal composition distribution (BOCD) polyethylenes are polyethylene homopolymers or polyethylene copolymers, most commonly polyethylene copolymers. It is desirable that the polyethylenes have a broad orthogonal composition distribution, which provides enhanced balance of stiffness, toughness, and processability (S / T / P) to the polyethylenes and compositions comprising these polymers. Given that the polymers are a blend of molecules with different chain length distributions, the polymers with BOCD are branched polymers with the majority, if not all, branching occurring on the high molecular weight molecules of the polymer, which makes them less crystalline. This microstructure has a tendency to improve certain properties of products made from the BOCD type polymers, including the polyolefin composition described herein.

[0062] Ziegler-Natta ("ZN") produced polyethylenes tend not to have a BOCD type structure, with most short chain branching occurring on the low molecular weight portion of the molecules so produced. On the other hand, some metallocene polyethylenes can generally have a BOCD type structure. The value of BOCD polymers relative to conventional polymers is significant.

[0063] In embodiments of the present application, the BOCD polyethylene can have a "broad ortho-composition distribution" ("BOCD"). The broad ortho-composition distribution can be determined using fractionation techniques such as gel permeation chromatography-differential viscometer (GPC-DV), temperature rising elution fractionation-differential viscometer (TREF-DV) or cross-fractionation techniques. For example, WO 2015 / 123164 Al, which is incorporated herein by reference, discusses the TREF technique, providing a measurement of the bivariate mass distribution of the crystalline portion of the BOCD polyethylene.

[0064] The BOCD polyethylene of the present application comprises from about 70 mol% to about 99 mol% of units derived from ethylene, based on the total number of moles of polymer units of the BOCD polyethylene. The lower limit of the range of content of units derived from ethylene can be 70 mol%, 75 mol%, 80 mol%, 85 mol%, 90 mol%, 92 mol%, 94 mol%, 95 mol%, 96 mol%, 97 mol%, 98 mol%, or 99 mol%, based on the total number of moles of polymer units of the BOCD polyethylene. The upper limit of the range of content of units derived from ethylene can be 80 mol%, 85 mol%, 90 mol%, 92 mol%, 94 mol%, 95 mol%, 96 mol%, 97 mol%, 98 mol%, 99 mol%, 99.5 mol%, or 100 mol%, based on the total number of moles of polymer units of the BOCD polyethylene. Any of the above upper limit contents can be combined with any of the above upper limit contents; any of the above upper limit contents can be combined with any of the above lower limit contents; and any of the above upper limit contents can be combined with any of the above lower limit contents.

[0065] The BOCD polyethylene of the present application can have equal to or less than 30 mol% of polymer units derived from C3-C20 olefins, such as C3-C20 alpha-olefins, such as hexene or octene. The upper limit of the range of the content of polymer units derived from C3-C20 olefins can be 30 mol%, 25 mol%, 20 mol%, 15 mol%, 10 mol%, 8 mol%, 6 mol%, 5 mol%, 4 mol%, 3 mol%, 2 mol%, 1 mol%, or 0.5 mol%, based on the total number of moles of polymer units of the BOCD polyethylene. The lower limit of the range of the content of polymer units derived from C3-C20 olefins can be 0 mol%, 1 mol%, 2 mol%, 3 mol%, 4 mol%, 5 mol%, 6 mol%, 8 mol%, 10 mol%, 15 mol%, 20 mol%, or 25 mol%, based on the total number of moles of polymer units of the BOCD polyethylene. Any of the above upper limits can be combined with any of the above upper limits; any of the above upper limits can be combined with any of the above lower limits; and any of the above upper limits can be combined with any of the above lower limits.

[0066] According to embodiments of the present application, the BOCD polyethylene can have a density of 0.910 g / cm3to 0.925 g / cm3, as measured according to ASTM D-792 or ASTM D-1505. 3 3 , or 0.910 g / cm3to 0.923 g / cm3, 3 3 , 0.910 g / cm3to 0.920 g / cm3, 3 3 , 0.915 g / cm3to 0.921 g / cm3, 3 3 , 0.910 g / cm3to 0.918 g / cm3, 3 3 , 0.912 g / cm3to 0.918 g / cm3, 3 3 , or 0.912 g / cm3to 0.917 g / cm3. 3 3 .

[0067] According to embodiments of the present application, the BOCD polyethylene has a melt index (MI, or I 2.16 ) of about 0.5 g / 10 min to about 3.0 g / 10 min, preferably about 1.0 g / 10 min to about 2.0 g / 10 min, as measured according to ASTM D-1238-E (190°C / 2.16 kg).

[0068] ​​​​​​​The term "composition distribution breadth index (CDBI)" means the weight percent of copolymer molecules having a comonomer content within 50% of the median molar comonomer content. The BOCD polyethylenes of the present application generally have a broad composition distribution as measured by the composition distribution breadth index (CDBI).

[0069] The CDBI of a copolymer can be measured using techniques known in the art. The CDBI of a copolymer is readily determined using well-known techniques for separating individual fractions of a copolymer sample. One such technique is temperature rising elution fractionation (TREF), as described in Wild et al., J. Poly. Sci., Poly. Phys. Ed., Vol. 20, pp. 441-455 (1982), which is incorporated herein by reference. Generally, a high CDBI indicates that most of the fractions elute in a short period of time (small temperature range), and the comonomer distribution is narrow; a low CDBI indicates that most of the fractions elute over a long period of time (large temperature range), indicating a broad comonomer distribution.

[0070] Details regarding the determination of the CDBI of a copolymer are known to those skilled in the art, see, for example, PCT Patent Application WO 1993 / 003093, published February 18, 1993, which is incorporated herein by reference, the description of CDBI therein, e.g., the description on page 13, paragraph 4, the transition on pages 14-15, the transition on pages 18-19, etc.

[0071] According to embodiments of the present application, the BOCD polyethylenes are characterized as having a composition distribution breadth index (CDBI) from about 25 wt% to about 55 wt%.

[0072] Materials and methods for making BOCD polyethylenes have been described in, for example, U.S. Patent No. 6,956,088, specifically Example 1; U.S. Patent Application Publication No. 2009 / 0297810, specifically Example 1; U.S. Patent Application Publication No. 2015 / 0291748, specifically Examples PE1-PE5; and WO 2014 / 099356, specifically PE3 mentioned on page 12 and in the Examples, including the use of a silica-supported hafnium transition metallocene / methylaluminoxane catalyst system, such as described in U.S. Patent Nos. 6,242,545 and 6,248,845, specifically Example 1.

[0073] Many BOCD polyethylenes are commercially available. One or more BOCD polyethylenes are commercially available from ExxonMobil Chemical Company, Houston, TX, and under the trade designation Exceed®. One or more BOCD polyethylenes are commercially available from The Dow Chemical Company, Midland, MI, and under the trade designation Affinity®. TMXP metallocene polyethylene (mPE) for sale. Exceed TM XPmPE offers advantageous properties such as dart impact strength, resistance to flexural cracking and longitudinal (MD) tearing, and maintaining stiffness at lower densities. TM XP mPE also offers a good balance of melt strength, toughness, stiffness and sealing ability, making this type of polymer ideal for applications such as blown film / sheet molding.

[0074] Other BOCD polyethylenes, including EXT515, are commercially available from ExxonMobil Chemical Company, Houston, TX.

[0075] The following BOCD polyethylene is used in the embodiments of this application:

[0076] Exceed TM XP 8318 is a polyethylene purchased from ExxonMobil Chemical Company, Houston, TX. It is a copolymer of ethylene and 1-hexene and has a strength of 0.918 g / cm³ as measured according to ASTM D792. 3 The density and melt index of 1.0 g / 10 min as measured according to ASTM D1238-E (190℃ / 2.16 kg), and composition distribution width index (CDBI) of approximately 38.6% by weight;

[0077] EXT515 is a polyethylene purchased from ExxonMobil Chemical Company, Houston, TX. It is a copolymer of ethylene and 1-hexene and has a strength of 0.915 g / cm³ as measured according to ASTM D1505. 3 It has a density and a melt index of 1.4 g / 10 min as measured according to ASTM D1238-E (190℃ / 2.16 kg), and a composition distribution width index (CDBI) of approximately 43% by weight.

[0078] polypropylene

[0079] According to the present invention, the polypropylene is selected from homopolymer polypropylene and impact polypropylene.

[0080] The polyolefin composition of the present invention includes one or more polypropylenes. The polypropylene may be a propylene homopolymer or a propylene copolymer.

[0081] "Polypropylene" is a polymer containing at least 50 mol%, for example at least 60 mol%, at least 70 mol%, at least 80 mol%, at least 90 mol%, or even 100 mol% of polymer units derived from propylene, based on the total number of moles of polymer units derived from polypropylene.

[0082] The polypropylene can have equal to or less than 50 mol% of polymer units derived from ethylene and / or one or more C4-C20 olefins, such as C4-C20 a-olefins, such as hexene or octene, based on the total moles of polymer units of the polypropylene. The upper limit of the range of the content of polymer units derived from C4-C20 olefins can be 50 mol%, 45 mol%, 40 mol%, 35 mol%, 30 mol%, 25 mol%, 20 mol%, 15 mol%, 10 mol%, 8 mol%, 6 mol%, 5 mol%, 4 mol%, 3 mol%, 2 mol%, 1 mol%, or 0.5 mol%, based on the total moles of polymer units of the polypropylene. The lower limit of the range of the content of polymer units derived from C4-C20 olefins can be 0 mol%, 0.5 mol%, 2 mol%, 3 mol%, 4 mol%, 5 mol%, 6 mol%, 8 mol%, 10 mol%, 15 mol%, 20 mol%, 25 mol%, 30 mol%, 35 mol%, 40 mol%, or 45 mol%, based on the total moles of polymer units of the polypropylene. Any of the above upper limits can be combined with any of the above upper limits; any of the above upper limits can be combined with any of the above lower limits; and any of the above upper limits can be combined with any of the above lower limits.

[0083] According to embodiments of the application, the polypropylene can be or include one or more homopolymers of PP (hPP), or one or more impact copolymers of PP (ICP), or any combination thereof.

[0084] Homopolymers of polypropylene (hPP)

[0085] In embodiments of the application, the polypropylene can be or include one or more homopolymers of polypropylene (hPP).

[0086] According to embodiments of the application, the homopolymers of polypropylene (hPP) can have a melt index from about 1 g / 10 min, about 1.2 g / 10 min, about 1.4 g / 10 min, about 1.6 g / 10 min, or about 1.8 g / 10 min to about 2 g / 10 min, about 2.2 g / 10 min, about 2.5 g / 10 min, about 2.8 g / 10 min, about 3 g / 10 min, about 3.5 g / 10 min, about 4 g / 10 min, about 4.5 g / 10 min, about 5 g / 10 min, about 5.5 g / 10 min, or about 6 g / 10 min, as determined according to ASTM D1238-L (230 °C / 2.16 kg). Combinations of any of the above upper limits with any of the below lower limits are also within the scope of the present application.

[0087] According to embodiments of the present application, the homopolymer of polypropylene (hPP) can have a density from about 0.8 g / cm 3 , about 0.82 g / cm 3 , about 0.84 g / cm 3 , about 0.85 g / cm 3 , about 0.86 g / cm 3 , or about 0.88 g / cm 3 to about 0.9 g / cm 3 , about 0.92 g / cm 3 , about 0.95 g / cm 3 , or about 0.98 g / cm 3 , as determined according to ASTM D792-13. Combinations of any of the above-mentioned upper limits with any of the below-mentioned lower limits are also within the scope of the present application.

[0088] According to embodiments of the present application, the homopolymer of polypropylene (hPP) can have a tensile strength at yield from about 20 MPa, about 25 MPa, about 30 MPa, or about 35 MPa to about 40 MPa, about 45 MPa, about 50 MPa, about 60 MPa, about 80 MPa, or about 100 MPa, as determined according to ASTM D638. Combinations of any of the above-mentioned upper limits with any of the below-mentioned lower limits are also within the scope of the present application.

[0089] The polypropylene homopolymer from Sinopec, T30S, i.e., “PP PPH-T03 (T30S) Sinopec / Drawn down” was used in the examples of the present application as the homopolymer of polypropylene (hPP).

[0090] The polypropylene homopolymer of “PP PPH-T03 (T30S) Sinopec / Drawn down” has the following property parameters:

[0091] Melt index: 3.2 g / 10 min, measured at 230 °C and 2.16 kg;

[0092] Isotactic isotacticity index: 97.2%;

[0093] Ash content: 0.02%;

[0094] Tensile strain at break: 498%;

[0095] Tensile strength at yield: 31.5 MPa;

[0096] Density: 0.900 g / cm 3 , as determined according to ASTM D792-13.

[0097] Impact Copolymer of Polypropylene (ICP)

[0098] In embodiments of the present application, the polypropylene can be or include one or more polypropylene impact copolymers (ICP).

[0099] According to embodiments of the present application, the polypropylene impact copolymer (ICP) can have a melt index from about 1 g / 10 min, about 2 g / 10 min, about 2.2 g / 10 min, about 2.5 g / 10 min, about 2.8 g / 10 min, about 3 g / 10 min, about 3.2 g / 10 min, about 3.5 g / 10 min to about 3.8 g / 10 min, about 4 g / 10 min, about 4.5 g / 10 min, about 5 g / 10 min, about 5.5 g / 10 min, or about 6 g / 10 min, as determined according to ASTM D1238-L (230 °C / 2.16 kg). Combinations of any of the above-mentioned upper limits with any of the above-mentioned lower limits are also within the scope of the present application.

[0100] According to embodiments of the present application, the polypropylene impact copolymer (ICP) can have a density from about 0.8 g / cm 3 , about 0.82 g / cm 3 , about 0.84 g / cm 3 , about 0.85 g / cm 3 , about 0.86 g / cm 3 , or about 0.88 g / cm 3 to about 0.9 g / cm 3 , about 0.92 g / cm 3 , about 0.95 g / cm 3 , or about 0.98 g / cm 3 , as determined according to ASTM D792-13. Combinations of any of the above-mentioned upper limits with any of the above-mentioned lower limits are also within the scope of the present application.

[0101] According to embodiments of the present application, the polypropylene impact copolymer (ICP) can have a tensile strength at yield from about 10 MPa, about 15 MPa, about 18 MPa, about 20 MPa, about 25 MPa, about 30 MPa, or about 35 MPa to about 40 MPa, about 45 MPa, about 50 MPa, about 60 MPa, about 80 MPa, or about 100 MPa, as determined according to ASTM D638. Combinations of any of the above-mentioned upper limits with any of the above-mentioned lower limits are also within the scope of the present application.

[0102] ExxonMobil TM PP7032E3 was used as the polypropylene impact copolymer (ICP) in embodiments of the present application, which is available from ExxonMobil Chemical Company, Houston, TX.

[0103] ExxonMobil TM PP7032E3 has the following performance parameters:

[0104] Melt Index: 4.0 g / 10 min, measured according to ASTM D1238-L (230°C / 2.16 kg);

[0105] Density: 0.900 g / cm 3 , measured according to ASTM D792-13;

[0106] Tensile Strength at Yield: 23.7 MPa, measured according to ASTM D638.

[0107] High Density Polyethylene

[0108] The high density polyethylene (HDPE) according to the present application has a density greater than 0.940 g / cm 3 and a melt index of about 0.5 g / 10 min to about 10 g / 10 min, wherein the density is measured according to ASTM D-1505 and the melt index is measured according to ASTM D1238-E (190°C / 2.16 kg).

[0109] ExxonMobil TM HDPE HTA 108 is used as the high density polyethylene in the embodiments of the present application, which is available from ExxonMobil Chemical Company, Houston, TX.

[0110] ExxonMobil TM HDPE HTA 108 has the following performance parameters:

[0111] Density: 0.961 g / cm 3 , measured according to ASTM D-1505;

[0112] Melt Index: 0.70 g / 10 min, measured according to ASTM D-1238-E (190°C / 2.16 kg).

[0113] Additives

[0114] According to embodiments of the present application, other additives can also be present in the polyolefin compositions and films of the present application.

[0115] These additives can include antioxidants (e.g., hindered phenolics and phosphites), stabilizers such as lactones and vitamin E, nucleating agents (alpha- and beta-nucleating agents), clarifiers, colorants (dyes or pigments), fillers (silica or talc), UV stabilizers, mold release agents, slip agents, tackifiers, antistatic agents, acid scavengers (e.g., calcium stearate), antiblocking agents, anti-blooming agents, polymeric processing aid masterbatch (PPA MB) additives / agents, hydrocarbon resins such as Oppera TM resins or combinations thereof. BRIEF DESCRIPTION OF DRAWINGS

[0116] Figure 1 A bar graph showing the MD Elongation at Break (%) for the following formulations: Pure Exceed XP 8318ML; 90 wt% Exceed XP 8318ML + 10 wt% T30S; 80 wt% Exceed XP 8318ML + 20 wt% T30S; 80 wt% Exceed XP 8318ML + 20 wt% ICP7032; and 80 wt% Exceed XP 8318ML + 20 wt% HTA 108, based on the weight of the monolayer film; and

[0117] Pure EXT 515; 80 wt% EXT 515 + 20 wt% T30S; 80 wt% EXT 515 + 20 wt% ICP7032; and 80 wt% EXT 515 + 20 wt% HTA 108, based on the weight of the monolayer film. Where ICP7032 is ExxonMobil PP7032E3, available from ExxonMobil Chemical Company, Houston, TX. TM

[0118] Figure 2 A bar graph showing the MD 1% Secant Modulus (MPa) for the following formulations: Pure Exceed XP 8318ML; 90 wt% Exceed XP 8318ML + 10 wt% T30S; 80 wt% Exceed XP 8318ML + 20 wt% T30S; 80 wt% Exceed XP 8318ML + 20 wt% ICP7032; and 80 wt% Exceed XP 8318ML + 20 wt% HTA 108, based on the weight of the monolayer film; and

[0119] ​Pure Exceed XP 8318ML; 90 wt% Exceed XP 8318ML + 10 wt% T30S; 80 wt% Exceed XP 8318ML + 20 wt% T30S; 80 wt% Exceed XP 8318ML + 20 wt% ICP7032; and 80 wt% Exceed XP 8318ML + 20 wt% HTA 108, based on the weight of the single layer film. Wherein ICP7032 is ExxonMobil PP7032E3, available from ExxonMobil Chemical Company, Houston, TX. TM Pure Exceed XP 8318ML; 90 wt% Exceed XP 8318ML + 10 wt% T30S; 80 wt% Exceed XP 8318ML + 20 wt% T30S; 80 wt% Exceed XP 8318ML + 20 wt% ICP7032; and 80 wt% Exceed XP 8318ML + 20 wt% HTA 108, based on the weight of the single layer film. Wherein ICP7032 is ExxonMobil PP7032E3, available from ExxonMobil Chemical Company, Houston, TX.

[0120] Figure 3 A bar chart showing the dart drop impact strength / thickness (g / µm) of the following formulations:

[0121] Pure Exceed XP 8318ML; 90 wt% Exceed XP 8318ML + 10 wt% T30S; 80 wt% Exceed XP 8318ML + 20 wt% T30S; 80 wt% Exceed XP 8318ML + 20 wt% ICP7032; and 80 wt% Exceed XP 8318ML + 20 wt% HTA 108, based on the weight of the single layer film. Wherein ICP7032 is ExxonMobil PP7032E3, available from ExxonMobil Chemical Company, Houston, TX.

[0122] Pure Exceed XP 8318ML; 90 wt% Exceed XP 8318ML + 10 wt% T30S; 80 wt% Exceed XP 8318ML + 20 wt% T30S; 80 wt% Exceed XP 8318ML + 20 wt% ICP7032; and 80 wt% Exceed XP 8318ML + 20 wt% HTA 108, based on the weight of the single layer film. Wherein ICP7032 is ExxonMobil PP7032E3, available from ExxonMobil Chemical Company, Houston, TX. TM Pure Exceed XP 8318ML; 90 wt% Exceed XP 8318ML + 10 wt% T30S; 80 wt% Exceed XP 8318ML + 20 wt% T30S; 80 wt% Exceed XP 8318ML + 20 wt% ICP7032; and 80 wt% Exceed XP 8318ML + 20 wt% HTA 108, based on the weight of the single layer film. Wherein ICP7032 is ExxonMobil PP7032E3, available from ExxonMobil Chemical Company, Houston, TX.

[0123] Figure 4 A bar chart showing the dart drop impact strength / thickness (g / µm) of the following formulations:

[0124] Pure EXT 515; 80 wt% of EXT 515 + 20 wt% of T30S; 80 wt% of EXT 515 + 20 wt% of ICP7032; and 80 wt% of EXT 515 + 20 wt% of HTA 108, based on the weight of the monolayer film. Wherein ICP7032 is ExxonMobil TM PP7032E3. DETAILED DESCRIPTION

[0125] In order to better understand the technical solutions of the present application, the applicant provides the following examples for illustration. The examples are only for the purpose of illustration and do not limit the protection scope of the present application in any way.

[0126] Measurement method

[0127] The present application uses the following measurement methods.

[0128]

[0129] Examples

[0130] Examples 1-2 are both monolayer films, and the thickness of the films is 25 μm. Examples 1-2 are both manufactured under the same cast process conditions.

[0131] Cast processing process: the set temperature of the extruder ABCDE screw is about 265°C, the set temperature of the distributor is about 265°C, and the set temperature of the die is about 265°C. The sample line speed is about 200 m / min.

[0132] Example 1

[0133] Table 1 compares various properties of monolayer films with the following different compositions: pure Exceed XP 8318ML; 80 wt% of Exceed XP 8318ML + 20 wt% of T30S; 80 wt% of Exceed XP 8318ML + 20 wt% of ICP7032; and 80 wt% of Exceed XP 8318ML + 20 wt% of HTA 108, based on the weight of the monolayer film. Wherein ICP7032 is ExxonMobil TM PP7032E3.

[0134] Table 1

[0135]

[0136] Wherein:

[0137] A indicates comparison to pure EXT 515;

[0138] B indicates comparison to 80 wt% EXT 515 + 20 wt% HTA 108 combination.

[0139] From Table 2, it can be seen that the addition of 20 wt% of homopolymer polypropylene T30S resulted in a 31.6% increase in MD 1% Secant Modulus, while the Dart Impact Strength / Thickness (g / μm) and the Puncture Strength (mN / μm) were significantly increased by 74% and 20.5%, respectively, as compared to the addition of 20 wt% of high density polyethylene HTA 108. This indicates that the use of homopolymer polypropylene instead of high density polyethylene significantly improved both the stiffness and toughness of the film.

[0140] From Table 2, it can be seen that the addition of 20 wt% of polypropylene impact copolymer ICP7032 resulted in a slight decrease in MD 1% Secant Modulus (about 10.2% decrease), while the Dart Impact Strength / Thickness (g / μm) and the Puncture Strength (mN / μm) were significantly increased by 256% and 19.4%, respectively, as compared to the addition of 20 wt% of high density polyethylene HTA 108. This indicates that the use of polypropylene impact copolymer instead of high density polyethylene significantly improved the toughness of the film while maintaining the stiffness substantially equivalent.

[0141] Example 2

[0142] Table 2 compares various properties of monolayer films of the following different compositions: pure EXT 515; 80 wt% EXT 515 + 20 wt% T30S; 80 wt% EXT 515 + 20 wt% ICP7032; and 80 wt% EXT 515 + 20 wt% HTA 108, based on the weight of the monolayer film. ICP7032 is an ExxonMobil TM PP7032E3.

[0143] Table 2

[0144]

[0145] wherein:

[0146] A indicates comparison to pure EXT 515;

[0147] B indicates comparison to 80 wt% EXT 515 + 20 wt% HTA 108 combination.

[0148] As can be seen from Table 2, the addition of 20 wt% of the homopolymer polypropylene T30S resulted in an increase of 37.4% in the MD 1% Secant Modulus, while maintaining the Pin Prick Strength (mN / pm) essentially the same, and a significant increase of 62.4% in the Dart Drop Impact Strength / Thickness (g / pm). This shows that the use of a homopolymer polypropylene instead of a high density polyethylene significantly increases both the stiffness and toughness of the film.

[0149] As can be seen from Table 2, the addition of 20 wt% of the impact copolymer of polypropylene ICP7032 resulted in an essentially the same MD 1% Secant Modulus (0.74% decrease), while the Dart Drop Impact Strength / Thickness (g / pm) and the Pin Prick Strength (mN / pm) were significantly increased by 132% and 2.0%, respectively. This shows that the use of an impact copolymer of polypropylene instead of a high density polyethylene significantly increases the toughness while maintaining the stiffness essentially the same.

[0150] All documents described herein, including any priority documents and / or testing procedures, are hereby incorporated by reference. It is expressly not admitted that any of the documents described herein or incorporated by reference are prior art to the present disclosure. It will be apparent to one of ordinary skill in the art that various modifications can be made to the specific embodiments described herein without departing from the spirit and scope of the disclosure. Thus, it is intended that the disclosure not be limited by the particular disclosure of the embodiments described above. Similarly, the term "comprising" is to be taken in its broadest possible context as open- ended, meaning that it includes the elements and steps recited but not excluding others. Likewise, the term "comprising" is to be taken in its broadest possible context as open- ended, meaning that it includes the elements and steps recited but not excluding others. Likewise, the term "comprising" is to be taken in its broadest possible context as open- ended, meaning that it includes the elements and steps recited but not excluding others.

[0151] For the sake of brevity, only certain ranges of values are explicitly disclosed herein. However, ranges of values that are not explicitly recited are to be understood as being implicitly described and covered by the disclosure. For example, every midpoint between an explicitly recited range can be described and covered as implicitly described ranges. Similarly, every point within a range, for example, every point within a range of values, is encompassed even though only certain precise ranges are explicitly recited. The same applies to every range of numerical values even if only a single value is explicitly recited.

Claims

1. A polyolefin composition comprising from 60 wt% to 95 wt% of a BOCD polyethylene and from 5 wt% to 40 wt% of a polypropylene, based on the weight of the polyolefin composition, wherein the BOCD polyethylene contains from 70 mol% to 99 mol% of polymer units derived from ethylene, based on the total number of moles of polymer units of the BOCD polyethylene, and a density from 0.91 g / cm 3 to 0.925 g / cm 3 measured according to ASTM D-792 or ASTM D-1505, and a melt index, I 2.16 measured according to ASTM D-1238-E at 190°C / 2.16 kg, and the BOCD polyethylene has a composition distribution breadth index (CDBI) from 25 wt% to 55 wt%, wherein the polypropylene is selected from the group consisting of a homopolymer of polypropylene and an impact copolymer of polypropylene and combinations thereof, wherein the homopolymer of polypropylene has a melt index from 1 g / 10 min to 6 g / 10 min, determined according to ASTM D1238-L at 230 °C / 2.16 kg, and wherein the impact copolymer of polypropylene has a melt index from 1 g / 10 min to 6 g / 10 min, determined according to ASTM D1238-L at 230 °C / 2.16 kg.

2. The polyolefin composition according to claim 1, wherein the BOCD polyethylene has a melt index I 2.16 measured according to ASTM D-1238-E at 190 °C / 2.16 kg.

3. The polyolefin composition according to any one of claims 1 to 2, wherein the homopolymer of polypropylene has one or more of the following properties: (1) a density from 0.8 g / cm3 3 to 0.98 g / cm3 3 as determined according to ASTM D792-13; and (2) a tensile strength at yield from 20 MPa to 100 MPa, determined according to ASTM D638.

4. The polyolefin composition according to any one of claims 1 to 2, wherein the impact copolymer of polypropylene has one or more of the following properties: (1) a density from 0.8 g / cm3 3 to 0.98 g / cm3 3 as determined according to ASTM D792-13; and (2) a tensile strength at yield from 10 MPa to 100 MPa, determined according to ASTM D638.

5. The polyolefin composition according to any one of claims 1 to 2, wherein the polyolefin composition has a machine direction (MD) 1% secant modulus greater than 200 MPa to less than 410 MPa, measured when a film comprising the polyolefin composition has a thickness of 25 pm, wherein the machine direction (MD) 1% secant modulus is measured according to ASTM D 882 method.

6. The polyolefin composition according to any one of claims 1 to 2, wherein the polyolefin composition comprising polypropylene has essentially the same dart impact strength / thickness value compared to a polyolefin composition identical in all other respects except that the polypropylene is replaced by high density polyethylene, wherein the unit of the dart impact strength / thickness value is g / pm, wherein the dart impact strength is measured according to ASTM D1709 method, wherein the high density polyethylene (HDPE) has a density of more than 0.940 g / cm 3 0.5 g / 10 min to 10 g / 10 min melt index, wherein the density is measured according to ASTM D-1505, the melt index is measured according to ASTM D1238-E at 190 °C / 2.16 kg. wherein the expression "essentially the same dart drop impact strength / thickness value" means that the dart drop impact strength / thickness values differ by ± 4%.

7. The polyolefin composition according to any one of claims 1 to 2, wherein the polyolefin composition comprising polypropylene has a dart impact strength / thickness value of greater than 10 % to less than 260 %, wherein the units of the dart impact strength / thickness value are g / µm, wherein the dart impact strength is measured according to ASTM D 1709 method, compared to a polyolefin composition identical in all other respects except that the polypropylene is replaced by a high density polyethylene, wherein the high density polyethylene (HDPE) has a density of greater than 0.940 g / cm 3 and a melt index of 0.5 g / 10 min to 10 g / 10 min, wherein the density is measured according to ASTM D-1505 and the melt index is measured according to ASTM D1238-E at 190 °C / 2.16 kg.

8. The polyolefin composition according to any one of claims 1 to 2, wherein the polyolefin composition comprising polypropylene has substantially the same needle penetration value compared to a polyolefin composition identical in all other respects except that the polypropylene is replaced by high density polyethylene, wherein the unit of the needle penetration value is mN / pm, wherein the needle penetration is measured according to CEN 14477 method, wherein the high density polyethylene (HDPE) has a density greater than 0.940 g / cm 3 0.5 g / 10 min to 10 g / 10 min melt index, wherein the density is measured according to ASTM D-1505, the melt index is measured according to ASTM D1238-E at 190 °C / 2.16 kg. wherein the expression "essentially the same needle penetration strength value" means that the needle penetration strength values differ by ± 3%.

9. The polyolefin composition according to any one of claims 1 to 2, wherein the polyolefin composition comprising polypropylene has a needle penetration strength value of greater than 4 % to less than 30 %, wherein the unit of the needle penetration strength value is mN / pm, wherein the needle penetration strength is measured according to CEN 14477 method, compared to a polyolefin composition identical in all other respects except that the polypropylene is replaced by high density polyethylene (HDPE), wherein the high density polyethylene (HDPE) has a density of greater than 0.940 g / cm 3 and a melt index of 0.5 g / 10 min to 10 g / 10 min, wherein the density is measured according to ASTM D-1505 and the melt index is measured according to ASTM D1238-E at 190 °C / 2.16 kg.

10. A polyolefin composition comprising from 60 wt% to 95 wt% of a BOCD polyethylene and from 5 wt% to 40 wt% of a polypropylene, based on the weight of the polyolefin composition, wherein the BOCD polyethylene contains 70 mol% to 99 mol% of polymer units derived from ethylene, based on the total number of moles of polymer units of the BOCD polyethylene, and a density of 0.918 g / cm 3 as measured according to ASTM D-792, and a melt index, I, of 1.0 g / 10 min 2.16 as measured according to ASTM D-1238-E at 190°C / 2.16 kg, and the BOCD polyethylene has a Composition Distribution Breadth Index (CDBI) of 38.6 wt%, or wherein the BOCD polyethylene contains 70 mol% to 99 mol% of polymer units derived from ethylene, based on the total number of moles of polymer units of the BOCD polyethylene, and a density of 0.915 g / cm 3 which is measured according to ASTM D1505, and a melt index I 2.16 which is measured according to ASTM D-1238-E at 190 °C / 2.16 kg, and the BOCD polyethylene has a composition distribution breadth index (CDBI) of 43 wt%, wherein the polypropylene is selected from the group consisting of a homopolymer of polypropylene and an impact copolymer of polypropylene and combinations thereof, wherein the homopolymer of polypropylene has a melt index of 3.2 g / 10 min, determined according to ASTM D1238-L at 230 °C / 2.16 kg, and wherein the impact copolymer of polypropylene has a melt index of 4.0 g / 10 min, determined according to ASTM D1238-L at 230 °C / 2.16 kg.

11. A film comprising the polyolefin composition according to any one of claims 1 to 10.

12. The film according to claim 11, consisting of the polyolefin composition according to any one of claims 1 to 10.

13. A film comprising a polyolefin composition, wherein the polyolefin composition comprises from 60 wt% to 95 wt% of a BOCD polyethylene and from 5 wt% to 40 wt% of a polypropylene, based on the weight of the polyolefin composition, wherein the BOCD polyethylene contains from 70 mol% to 99 mol% of polymer units derived from ethylene, based on the total number of moles of polymer units of the BOCD polyethylene, and a density from 0.91 g / cm 3 to 0.925 g / cm 3 as measured according to ASTM D-792 or ASTM D-1505, and a melt index, I 2.16 as measured according to ASTM D-1238-E at 190°C / 2.16 kg, and the BOCD polyethylene has a Composition Distribution Breadth Index (CDBI) from 25 wt% to 55 wt%, wherein the polypropylene is selected from the group consisting of a homopolymer of polypropylene and an impact copolymer of polypropylene and combinations thereof, wherein the homopolymer of polypropylene has a melt index from 1 g / 10 min to 6 g / 10 min, determined according to ASTM D1238-L at 230 °C / 2.16 kg, wherein the impact copolymer of polypropylene has a melt index from 1 g / 10 min to 6 g / 10 min, determined according to ASTM D1238-L at 230 °C / 2.16 kg, and wherein the film has a machine direction (MD) 1% secant modulus greater than 200 MPa to less than 410 MPa, measured when the film comprising the polyolefin composition has a thickness of 25 pm, wherein the machine direction (MD) 1% secant modulus is measured according to ASTM D 882 method.

14. The film according to claim 13, wherein the BOCD polyethylene has a melt index I of 1.0 g / 10 min to 2.0 g / 10 min 2.16 measured according to ASTM D-1238-E at 190 °C / 2.16 kg.

15. The film according to any one of claims 13 to 14, wherein the film comprising polypropylene has substantially the same Dart Impact Strength / Thickness value compared to a film identical in all other respects except that the polypropylene is replaced with high density polyethylene, wherein the units of the Dart Impact Strength / Thickness value are g / µm, wherein the Dart Impact Strength is measured according to ASTM D 1709 method, wherein the high density polyethylene (HDPE) has a density greater than 0.940 g / cm 3 and a melt index of from 0.5 g / 10 min to 10 g / 10 min, wherein the density is measured according to ASTM D-1505 and the melt index is measured according to ASTM D1238-E at 190 °C / 2.16 kg, wherein the expression "essentially the same dart drop impact strength / thickness value" means that the dart drop impact strength / thickness values differ by ± 4%.

16. The film according to any one of claims 13 to 14, wherein the film comprising polypropylene has a dart drop impact strength / thickness value greater than 10% to less than 260% compared to a film identical in all other respects except that the polypropylene is replaced with high density polyethylene, wherein the units of the dart drop impact strength / thickness value are g / µm, wherein the dart drop impact strength is measured according to ASTM D 1709 method, wherein the high density polyethylene (HDPE) has a density greater than 0.940 g / cm 3 and a melt index of 0.5 g / 10 min to 10 g / 10 min, wherein the density is measured according to ASTM D-1505 and the melt index is measured according to ASTM D1238-E at 190 °C / 2.16 kg.

17. The film according to any one of claims 13 to 14, wherein the film comprising polypropylene has substantially the same needle penetration strength value compared to a film which is identical except that the polypropylene is replaced by high density polyethylene, wherein the unit of the needle penetration strength value is mN / pm, wherein the needle penetration strength is measured according to CEN 14477 method, wherein the high density polyethylene (HDPE) has a density of more than 0.940 g / cm 3 and a melt index of from 0.5 g / 10 min to 10 g / 10 min, wherein the density is measured according to ASTM D-1505 and the melt index is measured according to ASTM D1238-E at 190 °C / 2.16 kg, wherein the expression "essentially the same needle penetration strength value" means that the needle penetration strength values differ by ± 3%.

18. The film according to any one of claims 13 to 14, wherein the film comprising polypropylene has a needle penetration strength value greater than 4% to less than 30% compared to a film identical in all other respects except that the polypropylene is replaced with high density polyethylene, wherein the units of needle penetration strength are mN / pm, wherein needle penetration strength is measured according to CEN 14477 method, wherein the high density polyethylene (HDPE) has a density greater than 0.940 g / cm 3 and a melt index of 0.5 g / 10 min to 10 g / 10 min, wherein density is measured according to ASTM D-1505 and melt index is measured according to ASTM D1238-E at 190 °C / 2.16 kg.

19. A film comprising a polyolefin composition, wherein the polyolefin composition comprises from 60 wt% to 95 wt% of a BOCD polyethylene and from 5 wt% to 40 wt% of a polypropylene, based on the weight of the polyolefin composition, wherein the BOCD polyethylene contains 70 mol% to 99 mol% of polymer units derived from ethylene, based on the total number of moles of polymer units of the BOCD polyethylene, and a density of 0.918 g / cm 3 measured according to ASTM D-792, and a melt index, I, of 1.0 g / 10 min 2.16 measured according to ASTM D-1238-E at 190°C / 2.16 kg, and the BOCD polyethylene has a Composition Distribution Breadth Index (CDBI) of 38.6 wt%, or wherein the BOCD polyethylene contains 70 mol% to 99 mol% of polymer units derived from ethylene, based on the total number of moles of polymer units of the BOCD polyethylene, and a density of 0.915 g / cm 3 which is measured according to ASTM D1505, and a melt index I 2.16 which is measured according to ASTM D-1238-E at 190 °C / 2.16 kg, and the BOCD polyethylene has a composition distribution breadth index (CDBI) of 43 wt%, wherein the polypropylene is selected from the group consisting of a homopolymer of polypropylene and an impact copolymer of polypropylene, and combinations thereof, wherein the homopolymer of polypropylene has a melt index of 3.2 g / 10 min, determined according to ASTM D1238-L at 230 °C / 2.16 kg, and wherein the impact copolymer of polypropylene has a melt index of 4.0 g / 10 min, determined according to ASTM D1238-L at 230 °C / 2.16 kg; and wherein the film has a machine direction (MD) 1% secant modulus greater than 200 MPa to less than 410 MPa, measured when the film comprising the polyolefin composition has a thickness of 25 pm, wherein the machine direction (MD) 1% secant modulus is measured according to ASTM D 882 method.

20. The method of manufacturing a film according to any one of claims 11-19, manufactured by a cast method.

21. A package comprising a film according to any one of claims 11-19.

22. The package according to claim 21, said package being selected from the group consisting of food packaging and industrial packaging.

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