High-density ethylene-based polymer using hybrid supported catalyst, and preparation method thereof

Abstract

The present invention relates to a high-density ethylene-based polymer exhibiting excellent processability due to the use of a hybrid catalyst composition, and a preparation method thereof, the present invention providing a high-density polyethylene-based polymer having excellent mechanical properties such as excellent optical properties, impact resistance and hardness, as well as excellent stretchability. The high-density ethylene-based polymer according to the present invention can provide a polyethylene-based polymer capable of biaxial stretching or simultaneous stretching.

Description

High-density ethylene polymer using a hybrid supported catalyst and its production method

[0001] The present invention relates to a high-density ethylene polymer exhibiting high processability using a hybrid catalyst composition and a method for producing the same.

[0002] Polyethylene is a polymer used in various containers, packaging films, fibers, pipes, packing, and paints, including shopping bags, greenhouses, fishing nets, cigarette wrappers, ramen packets, battery cases, car bumpers, and interior materials. Polyethylene's mechanical and thermal properties are influenced by its molecular weight and density, which in turn influences its application. Generally, lower density polyethylene polymers offer better transparency and impact strength, but they also exhibit lower physical properties such as heat resistance, hardness, and flexural modulus, as well as reduced chemical resistance. Conversely, higher density polyethylene polymers exhibit better heat resistance, hardness, and flexural modulus, and increased chemical resistance, but at the expense of lower transparency and impact strength.

[0003] Meanwhile, low-density polyethylene is mainly used as a packaging material due to its excellent elongation properties, but its mechanical properties, such as flexural modulus, are low, making it difficult to apply it alone as a packaging material. In addition, high-density polyethylene, which satisfies these mechanical properties, has a problem in that it cannot be manufactured into a packaging film due to its lack of elongation. Therefore, the packaging material using polyethylene is currently mainly used in the form of a multilayer packaging material in which a low-density polyethylene film is laminated with PET (Polyethylene terephthalate) or PA (Polyamide). Since this multilayer packaging material is not made of a single material, but is used as a laminate including PET or PA, it is difficult to recycle, and therefore, there was a problem in causing serious environmental pollution.

[0004] Therefore, there is a need for the development of technologies that can provide new high-density polyethylene polymers that can be processed and used as packaging materials as a single component. Furthermore, despite the use of high-density polyethylene, there is a need for a polyethylene resin that possesses sufficient mechanical properties while also exhibiting excellent extensibility. In other words, research is needed to develop a new single-material, high-density polyethylene that can be processed and used in food packaging, possessing both sufficient extensibility and superior impact strength and chemical resistance.

[0005] There is a pressing need for the development of high-density polyethylene and a manufacturing method thereof that address the aforementioned issues. Specifically, to manufacture high-density polyethylene suitable for use as a single packaging material, research is needed on a high-density polyethylene using a metallocene catalyst that simultaneously satisfies high mechanical properties, excellent chemical resistance, and high extensibility, as well as excellent molding processability.

[0006] The present invention provides a high-density polyethylene that can be used as a packaging film having excellent optical properties, impact resistance, hardness, and other excellent mechanical properties as a single polyethylene resin, and at the same time excellent stretchability.

[0007] The present invention relates to a method for producing ethylene and C4-C under a hybrid metallocene catalyst comprising a transition metal compound of the following chemical formulas 1 to 3. 20 A method for producing high-density polyethylene by polymerizing α-olefin is provided, wherein the hybrid metallocene catalyst is included in a molar ratio of Chemical Formula 1: Chemical Formula 2: Chemical Formula 3 = 1: 0.2 to 3: 1 to 7.

[0008] [Chemical Formula 1]

[0009]

[0010] [Chemical Formula 2]

[0011]

[0012] [Chemical Formula 3]

[0013]

[0014] (In the above chemical formulas 1 to 3, R a is C2-C6 alkylene, R b and R c are each independently C1-C6 alkylene, R1, R2, R3, R4 and R5 are C1-C5 alkyl, X is halogen, m, m1 and m2 are integers from 0 to 4, n is an integer from 0 to 3, and o is an integer from 1 to 4.)

[0015] In one example of the present invention, the C4-C 20 The α-olefin may be a C5-C8 α-olefin, specifically 1-hexene.

[0016] In one example of the present invention, the hybrid metallocene catalyst may be a supported catalyst in which a transition metal compound and a cocatalyst are supported on a carrier.

[0017] In one example of the present invention, the cocatalyst may be at least one selected from the group consisting of compounds represented by chemical formulae 7 to 9.

[0018] [Chemical Formula 7]

[0019]

[0020] [Chemical Formula 8]

[0021]

[0022] [Chemical Formula 9]

[0023] [LH] + [Z(A)4] - or [L] + [Z(A)4] -

[0024] (In the above chemical formulas 7 to 9, n is an integer greater than or equal to 2, R6 is halogen, C1-C 20 C1-C substituted with alkyl or halogen 20is an alkyl group, D is aluminum (Al) or boron (B), and R7, R8 and R9 are each independently halogen, C1-C 20 Straight or branched chain alkyl group, C1-C substituted with halogen 20 Alkyl group or C1-C 20 is an alkoxy group, L is a neutral or cationic Lewis base, [LH] + and [L] + is a Bronsted acid, Z is a group 13 element, and A is C6-C 20 Aryl group or C1-C 20 It is an alkyl group.)

[0025] In one example of the present invention, the carrier may be at least one selected from the group consisting of silica, aluminum oxide, and magnesium oxide.

[0026] The present invention relates to a process for producing ethylene and C4-C under a hybrid metallocene catalyst. 20 A high-density polyethylene manufactured by polymerizing a monomer containing an α-olefin, wherein the high-density polyethylene has a density of 0.94 g / cm3 or more, a PDI of 30 or more, and is capable of being stretched 4 times or more in the MD (Machine Direction) at a speed of 200 % / s at 120 to 130°C and then sequentially biaxially stretched 4 times or more in the TD (Transverse Direction), or of being simultaneously biaxially stretched 4x4 times or more in the MD (Machine Direction) and TD (Transverse Direction).

[0027] In one example of the present invention, the chemical formula 1 may be a transition metal compound represented by the following chemical formula 4.

[0028] [Chemical Formula 4]

[0029]

[0030] In one example of the present invention, the chemical formula 2 may be a transition metal compound represented by the following chemical formula 5.

[0031] [Chemical Formula 5]

[0032]

[0033] In one example of the present invention, the chemical formula 3 may be a transition metal compound represented by the following chemical formula 6.

[0034] [Chemical Formula 6]

[0035]

[0036] In one example of the present invention, the high-density polyethylene resin may have a Melt Flow Rate (MFR) of 40 or more.

[0037] In one example of the present invention, the high-density polyethylene resin may have a crystallinity (Xc) of 80% or less.

[0038] The present invention provides a high-density polyethylene film comprising the above-described high-density polyethylene resin.

[0039] In one example of the present invention, the high-density polyethylene film may have a haze of 25% or less as measured according to ASTM D1003.

[0040] In one example of the present invention, the high-density polyethylene film may have a transparency of 70% or more as measured according to ASTM D1003.

[0041] In one example of the present invention, the high-density polyethylene film may have an impact strength of 120 gf or more as measured according to ASTM D1709.

[0042] The present invention can provide a high-density polyethylene polymer capable of sequential biaxial stretching or simultaneous biaxial stretching at a high magnification using the above hybrid metallocene catalyst, and a method for producing the same.

[0043] In addition, the present invention can provide a high-density polyethylene polymer having excellent optical properties, impact resistance, hardness, and other excellent mechanical properties, as well as excellent processability, and a method for producing the same.

[0044] In addition, the present invention can provide a high-density polyethylene polymer and a method for producing the same using a metallocene catalyst capable of biaxial stretching or simultaneous stretching at a high magnification, for example, simultaneous and sequential stretching at least 4 times in the MD and TD directions.

[0045] Unless otherwise defined herein, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0046] As used herein, the singular forms of terms may be construed to include the plural forms as well, unless otherwise specified.

[0047] The expressions “include,” “comprises,” “contains,” “has,” and “characterizes” mentioned in this specification are open-ended descriptions having equivalent meanings and do not exclude additional elements, materials, or processes not listed.

[0048] The unit of % used in this specification without special mention means weight % unless otherwise defined.

[0049] Below, the present disclosure will be described in detail. However, this is merely exemplary and the present disclosure is not limited to the specific embodiments described as examples.

[0050] Polyethylene polymers are used as packaging materials in various industries. When used as packaging materials, low-density polyethylene, which has excellent processability and stretchability, is used with other resin films. However, low-density polyethylene has poor mechanical properties, so it is used by laminating it with resin films such as PET (Polyethylene terephthalate) or PA (Polyamide) or polyamide. In this case, since it is a laminate of different materials, it cannot be recycled, which causes many environmental problems and limits its use.

[0051] To solve this problem, there have been attempts to apply high-density polyethylene, which has excellent mechanical properties, to packaging materials. However, while mechanical strength and chemical resistance have increased, transparency and elongation properties are poor, and film elongation is insufficient, so there are still problems in using it as a single packaging material.

[0052] To overcome this, various high-density polyethylene polymers using metallocene catalysts have been developed, but it has not been possible to produce high-density polyethylene that has sufficient heat resistance, hardness, flexural modulus, and chemical resistance, while also satisfying transparency and biaxial stretching characteristics.

[0053] The present invention has solved the above problems, and has produced high-density polyethylene having mechanical strength and stretchability as a packaging material, for example, high magnification of sequential biaxial stretching and simultaneous biaxial stretching, using a specific hybrid metallocene catalyst, and has also invented a method for producing the same, thereby completing the present invention.

[0054] The present invention relates to a process for producing ethylene and C4-C under a hybrid metallocene catalyst comprising the following chemical formulas 1 to 3. 20 A method for producing high-density polyethylene for packaging materials having excellent extensibility and mechanical properties and a density of 0.94 g / cm3 or more by polymerizing α-olefin is provided.

[0055] [Chemical Formula 1]

[0056]

[0057] [Chemical Formula 2]

[0058]

[0059] [Chemical Formula 3]

[0060]

[0061] (In the above chemical formulas 1 to 3, R a is C2-C6 alkylene, and R b and R c are each independently C1-C6 alkylene, R1, R2, R3, R4 and R5 are C1-C5 alkyl, X is halogen, m, m1 and m2 are integers from 0 to 4, n is an integer from 0 to 3, and o is an integer from 1 to 4.)

[0062] For example, the hybrid metallocene catalyst may contain chemical formula 1: chemical formula 2: chemical formula 3 in a molar ratio of 1: 0.2 to 3: 1 to 7, preferably 1: 0.2 to 1.5: 1 to 6, but is not limited thereto. When included in the above-described range, it may exhibit properties advantageous for application to polyethylene packaging materials.

[0063] For example, the ratio of the chemical formulas 1 to 3 includes the meaning that the molar ratio of chemical formula 2 to chemical formula 1 may be 1:0.2 to 3, and the molar ratio of chemical formula 3 to chemical formula 1 may be 1:1 to 7.

[0064] The method for producing high-density polyethylene according to the present invention can produce high-density polyethylene that is transparent and has high processability while exhibiting high mechanical properties such as sufficient heat resistance, impact strength, and hardness, and thus has the effect of providing a method for producing high-density polyethylene applicable to packaging materials.

[0065] Specifically, in the case of polyethylene manufactured with a conventional metallocene catalyst, there was a problem that when mechanical properties such as heat resistance, impact strength, and hardness were satisfied, the biaxial stretching characteristics were poor, and when the stretching characteristics were high and high processability was satisfied, the mechanical properties were poor.

[0066] However, using the hybrid metallocene having the above composition ratio according to the present invention, ethylene and C4-C 20 High-density polyethylene manufactured from α-olefin can be manufactured to have both mechanical properties and biaxial stretching characteristics.

[0067] In addition, the hybrid metallocene catalyst according to the present invention has excellent activity, thereby enabling stable operation in the production of high-density polyethylene, and thus has a process advantage in that high-density polyethylene can be continuously produced.

[0068] As an example, in the hybrid metallocene catalyst, the transition metal compound of chemical formula 1 may be a transition metal compound of chemical formula 4 below.

[0069] [Chemical Formula 4]

[0070]

[0071] The transition metal compound of the above chemical formula 4 exhibits very high catalytic activity, and the polyethylene produced has the characteristic of being able to exhibit high biaxial stretching properties.

[0072] As an example, in the hybrid metallocene catalyst, the transition metal compound of the chemical formula 2 may be a transition metal compound of the following chemical formula 5.

[0073] [Chemical Formula 5]

[0074]

[0075] The transition metal compound of the above chemical formula 5 can exhibit high comonomer incorporation during the production of a polymer.

[0076] As an example, in the hybrid metallocene catalyst, the transition metal compound of the chemical formula 3 may be a transition metal compound of the following chemical formula 6.

[0077] [Chemical Formula 6]

[0078]

[0079] The transition metal compound of the above chemical formula 6 can exhibit a high comonomer mixing, can form a high molecular weight polymer during the production of a polymer, and can improve high mechanical properties such as impact strength and flexural strength.

[0080] As an embodiment, when the hybrid metallocene catalyst of the present invention comprises chemical formulae 4 to 6, the polyethylene polymer produced from the metallocene catalyst exhibits mechanical strength and biaxial stretching properties that are more advantageous for use in a substrate layer included in a multilayer packaging material, and thus is more preferred.

[0081] In one example, the hybrid metallocene catalyst of the present invention may be a supported catalyst in which a transition metal compound and a cocatalyst are supported on a carrier.

[0082] The above cocatalyst may include the following chemical formulas 7 to 9.

[0083] [Chemical Formula 7]

[0084]

[0085] [Chemical Formula 8]

[0086]

[0087] [Chemical Formula 9]

[0088] [LH] + [Z(A)4] - or [L] + [Z(A)4] -

[0089] (In the above chemical formulas 7 to 9, n is an integer greater than or equal to 2, R6 is halogen, C1-C 20 C1-C substituted with alkyl or halogen 20is an alkyl group, D is aluminum (Al) or boron (B), and R7, R8 and R9 are each independently halogen, C1-C 20 Straight or branched chain alkyl group, C1-C substituted with halogen 20 Alkyl group or C1-C 20 is an alkoxy group, L is a neutral or cationic Lewis base, [LH] + and [L] + is a Bronsted acid, Z is a group 13 element, and A is C6-C 20 Aryl group or C1-C 20 It is an alkyl group.)

[0090] The compound represented by the above chemical formula 7 may be at least one selected from the group consisting of methylaluminoxane, ethylaluminoxane, isobutylaluminoxane, and butylaluminoxane, but is not limited thereto.

[0091] The compound represented by the above chemical formula 8 may be, for example, at least one selected from the group consisting of trimethylaluminum, triethylaluminum, triisobutylaluminum, tripropylaluminum, tributylaluminum, dimethylchloroaluminum, triisopropylaluminum, tri-s-butylaluminum, tricyclopentylaluminum, tripentylaluminum, triisopentylaluminum, trihexylaluminum, trioctylaluminum, ethyldimethylaluminum, methyldiethylaluminum, triphenylaluminum, tri-p-tolylaluminum, dimethylaluminum methoxide, dimethylaluminum ethoxide, trimethylboron, triethylboron, triisobutylboron, tripropylboron, and tributylboron, but is not limited thereto.

[0092] The compound represented by the above chemical formula 9 is, for example, triethylammonium tetraphenylboron, tributylammonium tetraphenylboron, trimethylammonium tetraphenylboron, tripropylammonium tetraphenylboron, trimethylammonium tetra(p-tolyl)boron, trimethylammonium tetra(o,p-dimethylphenyl)boron, tributylammonium tetra(p-trifluoromethylphenyl)boron, trimethylammonium tetra(p-trifluoromethylphenyl)boron, tributylammonium tetrapentafluorophenylboron, N,N-diethylanilinium tetraphenylboron, N,N-diethylanilinium tetrapentafluorophenylboron, diethylammonium tetrapentafluorophenylboron, triphenylphosphonium tetraphenylboron, trimethylphosphonium tetraphenylboron, triethylammonium tetraphenylaluminum, tributylammonium tetraphenylaluminum, Trimethylammonium tetraphenylaluminum, tripropylammonium tetraphenylaluminum, trimethylammonium tetra(p-tolyl)aluminum, tripropylammonium tetra(p-tolyl)aluminum, triethylammonium tetra(o,p-dimethylphenyl)aluminum, tributylammonium tetra(p-trifluoromethylphenyl)aluminum, trimethylammonium tetra(p-trifluoromethylphenyl)aluminum, tributylammonium tetrapentafluorophenylaluminum, N,N-diethylanilinium tetraphenylaluminum, N,N-diethylanilinium tetrapentafluorophenylaluminum, diethylammonium tetrapentatetraphenylaluminum, triphenylphosphonium tetraphenylaluminum, trimethylphosphonium tetraphenylaluminum, tripropylammonium tetra(p-tolyl)boron, It may be at least one selected from the group consisting of triethylammonium tetra(o,p-dimethylphenyl)boron, tributylammonium tetra(p-trifluoromethylphenyl)boron, triphenylcarbonium tetra(p-trifluoromethylphenyl)boron, and triphenylcarbonium tetrapentafluorophenylboron.

[0093] The above carrier may be one or more selected from the group consisting of silica, aluminum oxide, and magnesium oxide, but is not limited thereto.

[0094] The above hybrid metallocene catalyst may contain 0.001 to 10 mmol, or 0.001 to 1 mmol, of three kinds of transition metal compounds comprising the chemical formulas 1 to 3 based on 1 g of the carrier, and may contain 1 to 20 mmol, or 2 to 15 mmol, of a cocatalyst based on 1 g of the carrier, but is not necessarily limited thereto.

[0095] In one example, the carrier may have an average particle size of, but is not limited to, 10 to 250 μm, 10 to 150 μm, or 20 to 100 μm.

[0096] The micropore volume of the above carrier may be, but is not limited to, 0.1 to 10 ml / g, 0.5 to 5 ml / g, or 1.0 to 3.0 ml / g.

[0097] In one example, the hybrid metallocene catalyst may be injected into the reactor at a rate of 0.1 g / h or more, 0.5 g / h or more, 10 g / h or less, or 5 g / h or less, for example, 0.1 to 10 g / h or 0.5 to 5 g / h, but is not limited thereto.

[0098] In one example, the high-density polyethylene may be manufactured by injecting hydrogen into a reactor together with a monomer. The hydrogen may be injected into the reactor at a rate of 0.1 g / h or more, 1 g / h or more, 5 g / h or more, 100 g / h or less, or 50 g / h or less, for example, 0.1 to 100 g / h or 1 to 50 g / h, but is not limited thereto.

[0099] In one example, the C4-C 20 α-olefins are C4-C 12 It may be an α-olefin, specifically C4-C 20The α-olefin may be at least one selected from the group consisting of 1-butene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene, 1-undecene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-itocene, 4,4-dimethyl-1-pentene, 4,4-diethyl-1-hexene, and 3,4-dimethyl-1-hexene. As a specific example, C4-C 20 The α-olefin may be, but is not necessarily limited to, 1-hexene.

[0100] In one example, the C4-C 20 α-olefin can be injected into the reactor at 50 g / h or more, 100 g / h or more, 150 g / h or more, 1500 g / h or less, or 1000 g / h or less, for example, 50 to 1500 g / h, or 100 to 1000 g / h, but is not limited thereto.

[0101] In one example, in the method for producing the high-density polyethylene, the molar ratio of hydrogen / ethylene may be 0.01 or more, 0.1 or more, 10 or less, or 5 or less, and may be, for example, 0.01 to 10, 0.1 to 5, but is not limited thereto.

[0102] In one example, in the method for producing the high-density polyethylene, the molar ratio of hexene / ethylene may be 0.01 or more, 0.1 or more, 10 or less, or 5 or less, for example, 0.01 to 10, 0.1 to 5, or a value between the above values, but is not limited thereto.

[0103] For example, ethylene and C4-C 20Polymerization of α-olefins can be carried out at a temperature of 50 to 200°C, 60 to 100°C or 60 to 90°C and a pressure of 1 to 50 bar, 1 to 30 bar or any of the above values ​​and any value therebetween, but is not limited thereto, and it is to be understood that the polymerization temperature and pressure may be appropriately changed depending on the reactants and reaction conditions.

[0104] For example, ethylene and C4-C 20 Polymerization of α-olefins may be a slurry-phase or gas-phase polymerization reaction, and when the polymerization is carried out in a liquid or slurry phase, a solvent may be further included. Specifically, the solvent may be exemplified by propane, butane, pentane, hexane, octane, decane, dodecane, cyclopentane, methylcyclopentane, cyclohexane, methylcyclohexane, benzene, toluene, xylene, dichloromethane, chloroethane, dichloroethane, chlorobenzene, etc., and these solvents may be mixed and used in a certain ratio, but are not limited thereto.

[0105] The present invention relates to a process for producing ethylene and C4-C under the above hybrid metallocene catalyst. 20 A high-density polyethylene resin can be provided which is manufactured by polymerizing a monomer containing an α-olefin, has a density of 0.94 g / cm3 or more, a PDI of 30 or more, and can be stretched 4 times or more in the MD (Machine Direction) at a speed of 200 % / s at 120 to 130°C and then sequentially biaxially stretched 4 times or more in the TD (Transverse Direction). In addition, the high-density polyethylene according to the present invention can provide a high-density polyethylene resin which can be simultaneously biaxially stretched 4 times or more in MD x TD under the conditions described above, not only in the sequential stretching described above, but also in simultaneous biaxial stretching.

[0106] In one embodiment, the density of the high-density polyethylene resin may be 0.94 g / cm3 or more, 0.96 g / cm3 or more, 0.99 g / cm3 or less, 0.97 g / cm3 or less, or 0.96 g / cm3 or less, for example, 0.94 to 0.99 g / cm3, 0.94 to 0.96 g / cm3, or any of the above values ​​and any value therebetween.

[0107] The above PDI may be 30 or more, 40 or more, 50 or more, 60 or more, 70 or less, 60 or less, 50 or less, 55 or less, 50 or less, 40 or less, for example, 30 to 70, 30 to 60, or any of the above values ​​and any value therebetween.

[0108] For example, the high-density polyethylene resin may have a weight average molecular weight of 50,000 to 20,000 g / mol, 70,000 to g / mol, or 90,000 to 15,000 g / mol, and a number average molecular weight of 2,000 to 10,000 g / mol, 3,000 to 7,000 g / mol, or 3,000 to 5,000 g / mol.

[0109] As another example, the high-density polyethylene resin may have a Z-weight average molecular weight of 200,000 to 500,000 g / mol, 250,000 to 500,000 g / mol, or 300,000 to 500,000 g / mol.

[0110] The high-density polyethylene resin according to the present invention can be stretched 4 times or more, 5 times or more, 7 times or more, or up to 20 times in the MD (Machine Direction), for example, 4 to 20 times, or 5 to 15 times, or any of the above values ​​and values ​​therebetween.

[0111] In addition, the high-density polyethylene resin may be stretched in the TD (Transverse Direction) by 4 times or more, 7 times or more, 9 times or more, or 20 times or less after stretching in the MD (Machine Direction) direction, for example, by 4 to 20 times, 7 to 15 times, or any of the above values ​​and values ​​therebetween.

[0112] In one example, as described above, the high-density polyethylene of the present invention is capable of not only sequential biaxial stretching in the MD direction and then in the TD direction, but also simultaneous biaxial stretching. Specifically, the high-density polyethylene resin according to the present invention can be simultaneously stretched in the MD (Machine Direction) and the TD (Transverse Direction) at a rate of 200 % / s at 120 to 130°C by a stretching ratio of 4 times or more, 5 times or more, 9 times or more, 15 times or more, or 20 times or less, for example, 4 to 20 times or values ​​therebetween. In particular, the fact that the high-density polyethylene resin of the present invention can be stretched in the above-described range can be said to be a remarkable feature that distinguishes it from conventional high-density polyethylene resins.

[0113] Specifically, conventional high-density polyolefin resins manufactured using metallocene catalysts have been prone to fracture or tearing during biaxial stretching. However, the high-density polyolefin resin according to the present invention is capable of sequential biaxial stretching and simultaneous biaxial stretching at the aforementioned ratio, and thus has processability exhibiting superior stretchability compared to conventional high-density polyethylene, thereby enabling it to be applied to polyethylene packaging materials and used as a single polyethylene packaging material.

[0114] That is, the high-density ethylene resin according to the present invention may solve the problem that conventional polyethylene-based packaging materials could not achieve high mechanical properties and elongation characteristics, making it difficult to manufacture packaging materials using only polyethylene components. Accordingly, the high-density ethylene resin has excellent mechanical properties and can easily manufacture packaging materials using a single material, so it may be preferred as a substitute for packaging materials with a laminated structure using low-density polyethylene, which was not recyclable, including conventional other resins.

[0115] Therefore, the high-density polyethylene resin according to the present invention has a remarkable effect in terms of economic and environmental protection in that it can be applied to polyethylene packaging materials to provide packaging materials that can be recycled.

[0116] In one embodiment, the high-density polyethylene according to the present invention may have a melting index (MFR) (MFI (21.6 kg) / MI (2.16 kg)) calculated by measuring the melting index (MI) at 190° C. under a load of 21.6 kg and a load of 2.16 kg, respectively, according to ASTM D 1238, of 40 or more, 50 or more, 60 or more, 70 or more, 100 or less, or 80 or less, for example, 60 to 100, 60 to 90, 60 to 80, or each of the above values ​​and values ​​therebetween.

[0117] In one embodiment, the high-density polyethylene according to the present invention may have a crystallinity (Xc) value measured using a differential scanning calorimeter (DSC, device name: DSC 2920, manufacturer: TA instrument) of 80% or less, 70% or less, 30% or more, 40% or more, 50% or more, for example, 30 to 80%, or 40 to 70%, or any of the above values ​​and any value therebetween.

[0118] That is, the high-density polyethylene resin according to the present invention satisfies the values ​​of density, PDI, MFR and crystallinity (Xc) described above and exhibits high optical properties and elongation properties, so that it has the effect of exhibiting properties that enable it to be used as a packaging film and a single resin product, despite being a high-density polyethylene.

[0119] Although this does not limit the interpretation, it can be interpreted that the high-density polyethylene has high hardness, chemical resistance, transparency, and biaxial stretching characteristics by having a high PDI value, low crystallinity, and high MFR while satisfying the above-described density range.

[0120] The present invention provides a high-density polyethylene film comprising the above-described high-density polyethylene resin.

[0121] The high-density polyethylene film of the present invention can be used in products requiring high mechanical properties and stretching properties, including high density, high PDI, low crystallinity, high MFR, and biaxial stretching properties, as it contains the high-density polyethylene resin described above, and in particular, it has the effect of being able to manufacture a single polyethylene packaging material by being applied to the polyethylene packaging material described above.

[0122] The high-density polyethylene film of the present invention can be manufactured by extruding and stretching the high-density polyethylene resin described above or by blow molding, but is not limited to any method that can form the high-density polyethylene resin into a film.

[0123] In one example, the high-density polyethylene film may have a haze measured according to ASTM D1003 of 25% or less, 24% or less, 23% or less, 20% or less, 15% or less, 1% or more, 5% or more, or 10% or more, for example, 1 to 25%, 5 to 25%, or any of the above values ​​and any value therebetween.

[0124] In one embodiment, the high-density polyethylene film may have a transparency as measured according to ASTM D1003 of at least 50%, at least 60%, at least 70%, at most 99%, at most 90%, at most 85%, for example from 50 to 99%, more specifically from 60 to 99%, or a value therebetween or between the values ​​therebetween.

[0125] Additionally, the high-density polyethylene film may have an impact strength measured according to ASTM D1709 of 100 gf or more, 110 gf or more, 120 gf or more, 150 gf or more, 200 gf or more, 250 gf or more, 300 gf or more, 350 gf or more, 390 gf or more, 400 gf or more, 430 gf or more, 600 gf or less, 500 gf or less, 450 gf or less, for example, 120 to 600 gf, 250 to 500 gf, or a value between the above values ​​or a value between the above values.

[0126] Since the high-density polyethylene film described above includes the high-density polyethylene resin, it can provide a high-quality high-density polyethylene film with a uniform surface and high strength by utilizing high elongation characteristics. In addition, the high-density polyethylene film exhibits low haze, high transparency, and impact strength, making it easily applicable to polyethylene products. Therefore, it not only has high commercialization value, but can also be very advantageously applied, especially, to the manufacture of polyethylene single packaging materials.

[0127] Hereinafter, embodiments of the present invention will be further described with reference to specific experimental examples. The examples and comparative examples included in the experimental examples are merely illustrative of the present invention and do not limit the scope of the appended claims. It will be apparent to those skilled in the art that various modifications and variations of the examples are possible within the scope and technical spirit of the present invention, and it is also natural that such modifications and variations fall within the scope of the appended claims.

[0128] [Manufacturing Example 1]

[0129]

[0130] 7.8 g of a complex transition metal compound including transition metal compound A (Dichloro[rac-ethylenebis(indenyl)]zirconium(IV), transition metal compound B (Diphenylmethylene-(3-butyl-cyclopentadienyl)(2,7-di-tert-butyl-9-fluorenyl)-zirconium(IV)-dichloride), and transition metal compound C (Diphenylmethylene-(cyclopentadienyl)(2,7-di-tert-butyl-9-fluorenyl)-zirconium(IV)-dichloride)) (the molar ratio of each catalyst compound was 1:0.5:1.8) was mixed with 1.1 kg of a toluene solution containing 10 wt% methylaluminum oxane (MAO) to prepare a mixed solution having an Al / Zr ratio of 150, and stirred at room temperature for 1 hour to prepare a transition metal compound.

[0131] 250 g of silica (XP2402) was placed in a reactor, 30 ml of purified toluene was added to prepare a silica slurry, and the transition metal compound solution was injected into the silica slurry and stirred in an oil bath at 75°C for 3 hours to prepare a metallocene catalyst solution. The metallocene catalyst solution was separated into solid and liquid, the supernatant was removed to isolate only the metallocene catalyst, and washed three times with toluene and dried in a vacuum at 60°C for 10 hours to recover 230 g of a mixed metallocene catalyst in powder form.

[0132] [Manufacturing Example 2]

[0133] In Manufacturing Example 1, 3.5 g of the complex transition metal compound was prepared in the same manner as in Manufacturing Example 1, except that the mixture was comprised of transition metal compound A: transition metal compound B: transition metal compound C in a ratio of 1:1.5:6.

[0134] [Manufacturing Example 3]

[0135] In Manufacturing Example 1, 12.3 g of the complex transition metal compound was manufactured in the same manner as in Manufacturing Example 1, except that the mixture included transition metal compound A: transition metal compound B: transition metal compound C in a ratio of 1:0.3:1.4.

[0136] [Comparative Manufacturing Example 1]

[0137] In Manufacturing Example 1, 5.9 g of the complex transition metal compound was prepared in the same manner as in Manufacturing Example 1, except that the mixture of transition metal compound A: transition metal compound B: transition metal compound C was included in a ratio of 1: 0.05: 1.8.

[0138] [Comparative Manufacturing Example 2]

[0139] In Manufacturing Example 1, 4 g of the complex transition metal compound was prepared in the same manner as in Manufacturing Example 1, except that the mixture included transition metal compound A: transition metal compound B: transition metal compound C in a ratio of 1:0.5:0.17.

[0140] [Comparative Manufacturing Example 3]

[0141]

[0142] The same procedure as in Example 1 was followed, except that a complex transition metal compound was prepared using 1.8 g of transition metal compound D ((n-butylcyclopentadienyl)(tetramethylcyclopentadienyl)zirconium chloride) and 5.0 g of transition metal compound B (Diphenylmethylene-(3-butyl-cyclopentadienyl)(2,7-di-tert-butyl-9-fluorenyl)-zirconium(IV)-dichloride).

[0143] [Comparative Manufacturing Example 4]

[0144]

[0145] The same procedure as in Example 1 was followed, except that a complex transition metal compound was prepared using 1.2 g of transition metal compound E (bis(n-propylcyclopentadienyl)zirconium chloride), 0.8 g of transition metal compound B (Diphenylmethylene-(3-butyl-cyclopentadienyl)(2,7-di-tert-butyl-9-fluorenyl)-zirconium(IV)-dichloride)), and 5 g of transition metal compound F (dimethylsilylene)bis(2-methyl-4-phenylindenyl)zirconium dichloride.

[0146] [Comparative Manufacturing Example 5]

[0147]

[0148] The same procedure as in Example 1 was followed, except that a complex transition metal compound was prepared using 1.8 g of transition metal compound G (bis(iso-butylcyclopentadienyl)zirconium chloride), 0.8 g of transition metal compound B (Diphenylmethylene-(3-butyl-cyclopentadienyl)(2,7-di-tert-butyl-9-fluorenyl)-zirconium(IV)-dichloride), and 3.8 g of transition metal compound F (dimethylsilylene)bis(2-methyl-4-phenylindenyl)zirconium dichloride.

[0149] [Example 1]

[0150] An ethylene / 1-hexene polymerization reaction was performed at 90°C using a continuous gas phase polymerization reactor consisting of a fluidized bed using the catalyst prepared in Manufacturing Example 1. The reaction conditions are described in Table 2 below.

[0151] [Example 2]

[0152] The same procedure as Example 1 was followed, except that the catalyst manufactured in Manufacturing Example 2 was used as the catalyst.

[0153] [Example 3]

[0154] The same procedure as Example 1 was followed, except that the catalyst manufactured in Manufacturing Example 3 was used as the catalyst.

[0155] [Example 4]

[0156] The same procedure was followed as in Example 1, except that the polymerization temperature was set at 80°C.

[0157] [Comparative Example 1]

[0158] The same procedure as Example 1 was followed, except that the catalyst manufactured in Comparative Manufacturing Example 1 was used as the catalyst.

[0159] [Comparative Example 2]

[0160] The same procedure as Example 1 was followed, except that the catalyst manufactured in Comparative Manufacturing Example 2 was used as the catalyst.

[0161] [Comparative Example 3]

[0162] The same procedure as Example 1 was followed, except that the catalyst manufactured in Comparative Manufacturing Example 3 was used as the catalyst.

[0163] [Comparative Example 4]

[0164] The same procedure as Example 1 was followed, except that the catalyst manufactured in Comparative Manufacturing Example 4 was used as the catalyst.

[0165] [Comparative Example 5]

[0166] The same procedure as Example 1 was followed, except that the catalyst manufactured in Comparative Manufacturing Example 5 was used as the catalyst.

[0167] Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Polymerization temperature (℃) 90 90 90 80 90 90 90 90 90 Catalyst injection amount (g / hr) 1.7 1.69 1.67 1.72 11.2 0.9 1.85 2.3 Hydrogen injection amount (g / hr) 18.00 31.69 23.44 18.00 15.12 17.00 18.00 10.86 5.96 Hexene injection amount (g / hr) 176 500 278 176 34 85 49 700 35 33 46 Hydrogen / ethylene molar ratio 1.14 1.53 1.34 1.14 0.84 0.77 1.09 0.29 0.09 Hexene / ethylene Molar ratio 0.46 0.44 0.41 0.46 0.79 0.47 1.01 0.93 0.87 Polymer production (㎏ / h) 7.99 6.96 7.18 7.65 7.74 7.54 7.59 8.87 9.64

[0168] The physical properties of the polymers manufactured in the above examples and comparative examples were measured as follows, and the results are shown in Table 2.

[0169] (1) Melt Flow Ratio (MFR)

[0170] According to ASTM D 1238, the melting index was measured at 190 ℃ with a load of 21.6 kg and a load of 2.16 kg, respectively, and the ratio (MI 21.6 / MI 2.16 ) was calculated.

[0171] (2) Density

[0172] Density was measured according to ASTM D 1505.

[0173] (3) Molecular weight

[0174] Gel permeation chromatography-FTIR (GPC-FTIR) of Polymer Char's model GPC-6 was used. Measurements were made at 160°C, and trichlorobenzene was used as the solvent.

[0175] (4) Thermal characteristics

[0176] Measurements were made using a differential scanning calorimeter (DSC, device name: DSC 2920, manufacturer: TA instrument). Specifically, the polymer was heated to 200°C, maintained at that temperature for 5 minutes, cooled to 20°C, and then increased again, with the temperature rising and falling rates each controlled to 20°C / min.

[0177] Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Transition metal compound combination ABCABCABCABCABCABCDBEBFGBF Transition metal compound molar ratio 1:0.5:1.8 1:1.5:6 1:0.3:1.4 1:0.5:1.8 1:0.00 5:1.8 1:0.5:0.17 1:1.5 1:0.25:1.25 1:0.5:1 * MI0.5810.8850.4881.460.951.80.730.620.73 * MFI36.6539.7534.75102.732.309016.3441.9070.80 *MFR63.0844.0671.270.3134.005022.3867.5896.98Density(g / ㎤)0.9460.9430.9590.9420.95600.940.94140.94600.9456Mz(g / ㏖)493,00039,7000517,000523,300388,200394,200412,000830,676792,108Mn(g / ㏖)4000346035602300620054001010061236208Mw(g / ㏖)1 35,300121,900142,900103,100134,70086,400156,600121,565116,840PDI33.8335.2440.1445.1421.816.1215.4619.8518.82Tm (℃)127.39136.31118.43123.07133.7122.5127.96127.33126.89Tc(℃)115.21117.21107.61112.7117.5112.8115,116.02115.73Xc (%)65.3178.3162.7459.537458.185.2168.8468.63* 2.16kg, MI measured at 190℃* 21.kg, MFI measured at 190℃* MFR=MFI / MI

[0178] The polyethylene polymers manufactured in the above examples and comparative examples were extruded as follows to manufacture a film, and the physical properties of the film are listed in Table 3 below.

[0179] (5) Method for manufacturing polyethylene film

[0180] The polyethylene polymers of Example 1 and Comparative Examples 1 to 5 were extruded at 245°C using a L / D 42DML 25mm twin-screw extruder. The die temperature was maintained at 265°C. The T-DIE was adjusted to a size of 30 to 35 cm and a thickness of 770 to 780 μm to manufacture a film.

[0181] (6) Sequential biaxial stretching processing

[0182] Biaxial stretching processing was performed using SDB's Model name PS002 equipment. First, a 10cm X 10cm 1mm sheet sample was manufactured using a press at 190℃. The manufactured sheet was heated in an oven at 120-125℃ for 300 seconds, then stretched in the MD (machine direction) at a speed of 200% / s, and then in the TD (traverse direction).

[0183] (7) Simultaneous biaxial stretching processing

[0184] Biaxial stretching processing was performed using Burckner's Model KARO 5.0 equipment. 9cm x 9cm specimens were manufactured using polymers. The manufactured specimens were simultaneously stretched in both the machine direction (MD) and traverse direction (TD) at a rate of 200% / s under heated conditions of 120 to 130°C.

[0185] (8) Haze measurement

[0186] Five measurements were taken per specimen according to ASTM D 1003, and the average value was reported.

[0187] (9) Clarity measurement

[0188] Five measurements were taken per specimen according to ASTM D 1003, and the average value was reported.

[0189] Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Simultaneous Biaxial Elongation MD X TD 7X77X77X77X7 fail Thickness (um) 13.7 5.28.2 13.7 fail Haze (%) 9.3 7.4 19.49.3 fail Clarity (%) 95.3 98.4 76.6 95.3 fail Impact Strength (gf) 397 259 432 397 fail Sequential Biaxial Elongation Thickness (um) 17.3 4.7 9.2 17.3 fail MD X TD 4X76X95X94X7 fail Haze % 22.2 14.8 23.8 22.2 fail Clarity (%)87.673.791.095.3failImpact strength(gf)397124365397fail

[0190] Referring to Tables 1 to 3, Examples 1 to 4, by including a hybrid metallocene catalyst comprising a transition metal compound of Chemical Formula 1 to 3, produced polyolefin resins by polymerizing ethylene and α-olefin had a high density of 0.94 g / cm3 or higher, and were all capable of high-magnification biaxial stretching. However, it was confirmed that the high-density polyethylene polymers produced by Comparative Examples 3 to 5, which were produced using a catalyst other than the specific catalyst mixture of the present invention, were broken and could not be stretched. Comparative Examples 1 and 2 included the transition metal compounds of Chemical Formula 1 to 3 of the present invention, but when the ratio of Chemical Formula 1: Chemical Formula 2: Chemical Formula 3 was not satisfied, stretching was impossible, resulting in breakage or tearing during stretching and making processing impossible. Therefore, it was confirmed that such biaxial stretching characteristics were exhibited by producing a high-density polyethylene polymer using the hybrid metallocene catalyst of the present invention including a specific ratio. These results are thought to be due to the complex influence of the weight average molecular weight, number average molecular weight, molecular weight distribution, MFR characteristics, thermal characteristics, mechanical properties, crystallinity, etc. of the polymer produced by the hybrid metallocene catalyst of the present invention.

[0191] Above, although an embodiment has been described in detail through examples and experimental examples, the scope of an embodiment is not limited to a specific example, and should be interpreted in accordance with the appended patent claims.

Claims

1. Ethylene and C4-C under a mixed metallocene catalyst including a transition metal compound of the following chemical formulas 1 to 3 20 A method for producing high-density polyethylene by polymerizing α-olefin, A method for producing high-density polyethylene, wherein the above hybrid metallocene catalyst is included in a molar ratio of Chemical Formula 1: Chemical Formula 2: Chemical Formula 3 = 1: 0.2 to 3: 1 to 7. [Chemical Formula 1] [Chemical Formula 2] [Chemical Formula 3] (In the above chemical formulas 1 to 3 R a is C2-C6 alkylene, R b and R c are each independently C1-C6 alkylene, R1, R2, R3, R4 and R5 are each independently C1-C5 alkyl, X is a halogen, m, m1 and m2 are integers from 0 to 4, n is an integer from 0 to 3, and o is an integer from 1 to 4.) 2. In paragraph 1, C4-C above 20 A method for producing high-density polyethylene, wherein the α-olefin is a C5-C8 α-olefin.

3. In paragraph 1, A method for producing high-density polyethylene, wherein the above chemical formula 1 is chemical formula 4, chemical formula 2 is chemical formula 5, and chemical formula 3 is chemical formula 6. [Chemical Formula 4] [Chemical Formula 5] [Chemical Formula 6] 4. In paragraph 1, The above method for producing high-density polyethylene is a method for producing high-density polyethylene, wherein the polymerization temperature is 60 to 90°C.

5. In paragraph 1, A method for producing high-density polyethylene, wherein the above hybrid metallocene catalyst is a supported catalyst in which a transition metal compound and a cocatalyst are supported on a carrier.

6. In paragraph 5, A method for producing high-density polyethylene, wherein the cocatalyst is at least one selected from the group consisting of compounds represented by chemical formulas 7 to 9. [Chemical Formula 7] [Chemical Formula 8] [Chemical Formula 9] [LH] + [Z(A)4] - or [L] + [Z(A)4] - (In the above chemical formulas 7 to 9, n is an integer greater than or equal to 2, R6 is halogen, C1-C 20 C1-C substituted with alkyl or halogen 20 It is an alkyl group, D is aluminum (Al) or boron (B), and R7, R8 and R9 are each independently halogen, C1-C 20 Straight or branched chain alkyl group, C1-C substituted with halogen 20 Alkyl group or C1-C 20 It is an alkoxy group, L is a neutral or cationic Lewis base, [LH] + and [L] + is a Bronsted acid, Z is a group 13 element, and A is C6-C 20 Aryl group or C1-C 20 It is an alkyl group.) 7. In paragraph 5, A method for producing high-density polyethylene, wherein the carrier is at least one selected from the group consisting of silica, aluminum oxide, and magnesium oxide.

8. Ethylene and C4-C under hybrid metallocene catalyst 20 A high-density polyethylene resin manufactured from α-olefin, wherein the high-density polyethylene resin has a density of 0.94 g / cm3 or more, a PDI of 30 or more, and is capable of being stretched 4 times or more in the MD (Machine Direction) at a speed of 200 % / s at 120 to 130°C and then sequentially biaxially stretched 4 times or more in the TD (Transverse Direction), or of being simultaneously biaxially stretched 4x4 times or more in the MD (Machine Direction) and TD (Transverse Direction).

9. In paragraph 8, The above hybrid metallocene catalyst is a high-density polyethylene resin comprising a transition metal compound of the following chemical formulas 1 to 3. [Chemical Formula 1] [Chemical Formula 2] [Chemical Formula 3] (In the above chemical formulas 1 to 3 R a is C2-C6 alkylene, R b and R c are each independently C1-C6 alkylene, R1, R2, R3, R4 and R5 are each independently C1-C5 alkyl, X is a halogen, m and m1 are integers from 0 to 4, n is an integer from 0 to 3, and o is an integer from 1 to 4.) 10. In paragraph 9, A high-density polyethylene resin comprising the above hybrid metallocene catalyst in a molar ratio of Chemical Formula 1: Chemical Formula 2: Chemical Formula 3 = 1: 0.2 to 3: 1 to 7.

11. In paragraph 8, C4-C above 20 α-Olefin is a high-density polyethylene resin that is a C5-C8 α-olefin.

12. In paragraph 8, The above high-density polyethylene resin is a high-density polyethylene resin having an MFR (Melt Flow Rate) of 40 or more.

13. In paragraph 8, The above high-density polyethylene resin is a high-density polyethylene resin having a crystallinity (Xc) of 80 or less.

14. A high-density polyethylene film containing the high-density polyethylene resin of Article 8.

15. In paragraph 14, The above high-density polyethylene film is a high-density polyethylene film having a haze of 25% or less as measured according to ASTM D1003.

16. In paragraph 14, The above high-density polyethylene film is a high-density polyethylene film having a transparency of 70% or more as measured according to ASTM D1003.

17. In paragraph 14, The above high-density polyethylene film is a high-density polyethylene film having an impact strength of 120 gf or more as measured according to ASTM D1709.

18. A packaging material manufactured from a film selected from any one of items 14 to 17.

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