Polyethylene composition

Abstract

The present invention provides a polyethylene composition comprising virgin polyethylene and recycled polyethylene [post consumer waste polyethylene (PCW PE)], and having excellent mechanical properties and improved environmental stress cracking resistance.

Description

polyethylene composition

[0001] Cross-citation with related application(s)

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2023-0118439, filed September 6, 2023, and Korean Patent Application No. 10-2024-0121054, filed September 5, 2024, the entire contents of which are incorporated herein by reference.

[0003]

[0004] The demand for polyethylene resin is increasing and it is being used in a variety of applications.

[0005]

[0006] Recently, with growing environmental concerns, regulations to curb carbon dioxide emissions are being strengthened. In particular, with environmental pollution caused by the increased use of plastics emerging as a serious problem, regulations at the manufacturing stage are being strengthened, including mandating the use of recycled resin, primarily in the United States. Accordingly, manufacturers are required to add a certain amount of recycled resin to products such as resin molded products, and eco-friendliness ratings are assigned based on the amount of recycled resin present.

[0007]

[0008] However, since recycled resin is already processed, its properties have already changed during the high-temperature processing process, resulting in significantly lower impact strength, tensile strength, chemical resistance, and thermal stability compared to existing virgin resin. To address this issue, attempts have been made to incorporate a certain level of virgin resin into compositions containing recycled resin. However, this method requires an excessive amount of virgin resin to minimize the deterioration of mechanical properties, and major property degradation issues such as environmental stress cracking resistance (ESCR) remain unresolved. Furthermore, this problem becomes more severe as the number of processing cycles increases.

[0009]

[0010] The present invention includes virgin polyethylene and recycled polyethylene (PCW PE, post consumer waste polyethylene), and aims to provide a polyethylene composition having excellent mechanical properties and improved environmental stress crack resistance.

[0011]

[0012] According to one embodiment of the invention, a polyethylene composition comprising virgin polyethylene and recycled polyethylene (PCW PE, Post consumer waste polyethylene) is provided, which satisfies the following (a) to (d).

[0013] (a) Density 0.949 g / cm 3 more,

[0014] (b) Melting index (MI) 2.16 , ASTM D 1238, 190 ℃, 2.16kg) 0.25 g / 10min or more,

[0015] (c) The complex viscosity (η*(ω500), complex viscosity) measured at a frequency (ω) of 500 rad / s is 600 Paㆍs or less,

[0016] (d) Environmental stress cracking resistance (ESCR) of 200 hours or more as measured according to ASTM D 1693 (Condition B, F50, Igepal 10%).

[0017]

[0018] According to the present invention, by optimizing the density, melt index, and complex viscosity (η*(ω500), complex viscosity) and increasing the environmental stress cracking resistance (ESCR), a polyethylene composition can be provided that includes both virgin polyethylene and recycled polyethylene (PCW PE, Post-consumer waste polyethylene) and has excellent mechanical properties and improved environmental stress cracking resistance.

[0019]

[0020] In the present invention, terms such as first, second, etc. are used to describe various components, and the terms are used only for the purpose of distinguishing one component from another.

[0021]

[0022] Furthermore, the terminology used herein is merely for the purpose of describing exemplary embodiments and is not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this specification, it should be understood that the terms "comprise," "include," or "have" indicate the presence of a feature, number, step, component, or combination thereof, but do not preclude the possibility of the presence or addition of one or more other features, numbers, steps, components, or combinations thereof.

[0023]

[0024] In addition, the terms "about," "substantially," and the like used throughout this specification are used in a meaning that is at or close to the numerical value when manufacturing and material tolerances inherent to the meanings mentioned are presented, and are used to prevent unscrupulous infringers from unfairly exploiting the disclosure in which exact or absolute values ​​are mentioned to aid understanding of the present invention.

[0025]

[0026] In addition, in this specification, "part by weight" means a relative concept that expresses the weight of a substance as a ratio based on the weight of the remaining substance. For example, in a mixture containing 50 g of substance A, 20 g of substance B, and 30 g of substance C, the amounts of substance B and substance C are 40 parts by weight and 60 parts by weight, respectively, based on 100 parts by weight of substance A.

[0027]

[0028] In addition, "% by weight" refers to an absolute concept that expresses the weight of a certain substance as a percentage of the total weight. In the mixture exemplified above, the contents of substance A, substance B, and substance C are 50% by weight, 20% by weight, and 30% by weight, respectively, out of 100% of the total weight of the mixture. In this case, the total content of each component does not exceed 100% by weight.

[0029]

[0030] The present invention is susceptible to various modifications and takes various forms. Specific embodiments are illustrated and described in detail below. However, this is not intended to limit the present invention to specific disclosed forms, but rather to encompass all modifications, equivalents, and alternatives falling within the spirit and technical scope of the present invention.

[0031]

[0032] Hereinafter, the present invention will be described in more detail.

[0033]

[0034] According to one embodiment of the invention, a polyethylene composition is provided that includes virgin polyethylene and recycled polyethylene (PCW PE, Post consumer waste polyethylene), while optimizing density and complex viscosity (η*(ω500)) and increasing environmental stress cracking resistance (ESCR), thereby realizing high loading strength with excellent mechanical properties when used as a blow container, while simultaneously securing excellent processability and high drop strength.

[0035]

[0036] Specifically, the polyethylene composition of the present invention includes virgin polyethylene and recycled polyethylene (PCW PE, Post consumer waste polyethylene), and satisfies the following (a) to (d).

[0037] (a) Density 0.949 g / cm 3 more,

[0038] (b) Melting index (MI) 2.16 , ASTM D 1238, 190 ℃, 2.16kg) 0.25 g / 10min or more,

[0039] (c) The complex viscosity (η*(ω500), complex viscosity) measured at a frequency (ω) of 500 rad / s is 600 Paㆍs or less,

[0040] (d) Environmental stress cracking resistance (ESCR) of 200 hours or more as measured according to ASTM D 1693 (Condition B, F50, Igepal 10%).

[0041]

[0042] Hereinafter, the polyethylene composition of the present invention will be described in more detail.

[0043]

[0044] The polyethylene composition of the present invention comprises virgin polyethylene and recycled polyethylene (PCW PE, Post consumer waste polyethylene), and has a density and melt index (MI) 2.16 ) and complex viscosity (η*(ω500), complex viscosity) are optimized, and environmental stress cracking resistance (ESCR) is increased.

[0045]

[0046] In particular, the polyethylene composition has a density of 0.949 g / cm 3 and for example, 0.949 g / cm 3 Ideally 0.954 g / cm 3 The polyethylene composition of the present invention can secure excellent density while including recycled polyethylene (PCW PE, Post consumer waste polyethylene), thereby realizing sufficient loading strength when used as a blow container, etc.

[0047]

[0048] The polyethylene composition of the present invention can simultaneously secure excellent processability and high drop strength by optimizing the melt index along with the density described above.

[0049]

[0050] The above polyethylene composition has a melt index (MI) 2.16 , ASTM D 1238, 190 ℃, 2.16 kg) is 0.25 g / 10 min or more, and may be, for example, 0.25 g / 10 min to 0.8 g / 10 min. Preferably, the melt index (MI) of the polyethylene composition 2.16, ASTM D 1238, 190 ℃, 2.16 kg) may be 0.7 g / 10 min or less, or 0.65 g / 10 min or less, or 0.6 g / 10 min or less, or 0.55 g / 10 min or less, or 0.5 g / 10 min or less, or 0.45 g / 10 min or less, or 0.42 g / 10 min or less, or 0.4 g / 10 min or less, or 0.38 g / 10 min or less, and may be 0.26 g / 10 min or more, or 0.27 g / 10 min or more, or 0.28 g / 10 min or more, or 0.29 g / 10 min or more. The polyethylene composition of the present invention may have a melt index (MI) as described above. 2.16 ) can simultaneously secure excellent mechanical properties that can exhibit high loading strength, as well as excellent processability and high drop strength.

[0051]

[0052] In addition, the polyethylene composition has a complex viscosity (η*(ω500), complex viscosity) measured at a frequency (ω) of 500 rad / s of 600 Paㆍs or less, and may be, for example, 500 Paㆍs or more and 600 Paㆍs or less. Preferably, the complex viscosity (η*(ω500), complex viscosity) of the polyethylene composition measured at a frequency (ω) of 500 rad / s may be 585 Paㆍs or less, 580 Paㆍs or less, 575 Paㆍs or less, 570 Paㆍs or less, 568 Paㆍs or less, 565 Paㆍs or less, 562 Paㆍs or less, or 560 Paㆍs or less, but 505 Paㆍs or more, 508 Paㆍs or more, 510 Paㆍs or more, 512 Paㆍs or more, 515 Paㆍs or more, 520 Paㆍs or more, 525 Paㆍs or more, 530 Paㆍs or more, or 535 Paㆍs or more. The polyethylene composition of the present invention has the complex viscosity (η*(ω500)) described above, and thus, when used as a blow container, it can simultaneously secure excellent mechanical properties, excellent processability, and high drop impact strength.

[0053]

[0054] In addition, the polyethylene composition has a complex viscosity (η*(ω300), complex viscosity) measured at a frequency (ω) of 300 rad / s of 850 Paㆍs or more, and may be, for example, 850 Paㆍs or more and 980 Paㆍs or less. Preferably, the complex viscosity (η*(ω300), complex viscosity) measured at a frequency (ω) of 300 rad / s of the polyethylene composition may be 852 Paㆍs or more, 855 Paㆍs or more, 858 Paㆍs or more, 860 Paㆍs or more, or 862 Paㆍs or more, and 950 Paㆍs or less, 920 Paㆍs or less, or 900 Paㆍs or less, 890 Paㆍs or less, or 890 Paㆍs or less.

[0055]

[0056] In addition, the polyethylene composition has a complex viscosity (η*(ω0.05), complex viscosity) measured at a frequency (ω) of 0.05 rad / s of 38,000 Paㆍs or more, and may be, for example, 38,000 Paㆍs or more and 53,500 Paㆍs or less. Preferably, the complex viscosity (η*(ω0.05), complex viscosity) of the polyethylene composition measured at a frequency (ω) of 0.05 rad / s may be 38200 Paㆍs or more, 38350 Paㆍs or more, 38500 Paㆍs or more, 38900 Paㆍs or more, 40000 Paㆍs or more, 42000 Paㆍs or more, or 45000 Paㆍs or more, and 53000 Paㆍs or less, 51500 Paㆍs or less, 50000 Paㆍs or less, 48000 Paㆍs or less, or 45000 Paㆍs or less.

[0057]

[0058] The polyethylene composition of the present invention has the complex viscosity (η*(ω300) and η*(ω0.05)) described above, so that it can simultaneously secure excellent mechanical properties and excellent processability when used as a blow container.

[0059]

[0060] The polyethylene composition of the present invention has a density and a melt index (MI) as described above. 2.16 ) and complex viscosity (η*(ω500), complex viscosity) are optimized, and environmental stress cracking resistance (ESCR) is increased.

[0061]

[0062] The polyethylene composition has an environmental stress cracking resistance (ESCR) of 200 hours or more, as measured according to ASTM D 1693 (Condition B, F50, Igepal 10%), and may be, for example, 200 hours or more and 500 hours or less. Preferably, the ESCR of the polyethylene composition may be 203 hours or more, or 210 hours or more, or 215 hours or more, or 220 hours or more, or 250 hours or more, or 260 hours or more, or 270 hours or more, or 280 hours or more, and may also be 400 hours or less, or 350 hours or less, or 320 hours or less, or 300 hours or less, or 288 hours or less. The polyethylene composition of the present invention, with the excellent ESCR characteristics described above, can simultaneously secure excellent mechanical properties, excellent processability, and high drop strength when used as a blow container.

[0063]

[0064] Specifically, the environmental stress cracking resistance (ESCR) is a value measured by measuring the time to F50 (50% failure) for a compression-molded sample having a thickness of 2 mm under Condition B conditions at a temperature of 50°C using 10% Igepal CO-630 Solution according to the method of ASTM D 1693-07.

[0065]

[0066] The polyethylene composition according to the present invention optimizes the density and complex viscosity (η*(ω500), complex viscosity) as described above, and increases the environmental stress cracking resistance (ESCR), thereby increasing the content of recycled polyethylene while achieving excellent impact strength, tensile strength, chemical resistance and thermal stability close to that of virgin resin, thereby realizing high loading strength with excellent mechanical properties when used as a blow container, while simultaneously securing excellent processability and high drop strength.

[0067]

[0068] Meanwhile, according to the present invention, the polyethylene composition includes virgin polyethylene and recycled polyethylene (PCW PE, Post consumer waste polyethylene), and as described above, the density and complex viscosity (η*(ω500)) are optimized, and the environmental stress cracking resistance (ESCR) is increased. As described below, the polyethylene composition includes virgin resin in which the ratio of low molecular weight regions is optimized while the ratio of high molecular weight regions in the molecular structure is strengthened along with the density.

[0069]

[0070] Specifically, the new polyethylene may be an ethylene homopolymer or an ethylene / alpha-olefin copolymer, and may be a dry blend of one or more or two or more of the above-described ethylene homopolymers or ethylene / alpha-olefin copolymers.

[0071]

[0072] For example, when one or more kinds of the above-described ethylene homopolymer and the ethylene / alpha-olefin copolymer are mixed (dry blended), the weight ratio of one or more kinds of the ethylene homopolymer and one or more kinds of the ethylene / alpha-olefin copolymer may be 1:99 to 99:1, or 5:95 to 95:5, or 10:90 to 90:10, or 15:85 to 85:15, or 20:80 to 80:20, or 25:75 to 75:25, or 30:70 to 70:30, or 35:65 to 65:35, or 40:60 to 60:40, or 45:55 to 55:45.

[0073]

[0074] The above alpha-olefin may be at least one selected from the group consisting of 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, and mixtures thereof.

[0075]

[0076] For example, when the new polyethylene is a copolymer, it may contain about 0.45 mol or less, or about 0.1 mol to about 0.45 mol, or about 0.4 mol or less, or about 0.2 mol to about 0.4 mol, or about 0.35 mol or less, or about 0.25 mol to about 0.35 mol, of alpha-olefin based on 1 mol of ethylene.

[0077]

[0078] Specifically, when the new polyethylene is a copolymer, 1-hexene can be used as the alpha-olefin copolymerized with ethylene.

[0079]

[0080] Preferably, the new polyethylene may be an ethylene homopolymer that does not include a separate copolymer, an ethylene / 1-hexene copolymer, or a dry blend of the above-described ethylene homopolymer and the ethylene / 1-hexene copolymer.

[0081]

[0082] Meanwhile, the new polyethylene has a density (ASTM D1505, 23 ℃) of 0.944 g / cm 3 or more than 0.944 g / cm 3 0.954 g / cm 3 It can be high density polyethylene (HDPE) that satisfies .

[0083]

[0084] More specifically, the density of the new polyethylene is 0.945 g / cm 3 or 0.946 g / cm 3 and 0.954 g / cm 3 or less, or 0.953 g / cm 3 It could be as follows:

[0085]

[0086] When the density of the above-mentioned virgin polyethylene satisfies the above-mentioned range, compatibility with recycled polyethylene can be improved, and when mixed with recycled polyethylene, deterioration of major physical properties such as ESCR can be minimized without using an excessive amount of virgin polyethylene resin.

[0087]

[0088] Meanwhile, in the GPC curve graph where the x-axis is log Mw and the y-axis is dw / dlogMw, the integral value of the region where Log Mw is 5.5 or more is 14% or less, or 5% or more to 14% or less, of the total integral value.

[0089]

[0090] Specifically, the integral value of the region where the Log Mw is 5.5 or more may be less than 14%, or 13.5% or less, or 13% or less, so as to secure excellent processability and high drop impact strength when mixing the virgin polyethylene and recycled polyethylene. However, when considering excellent mechanical properties at a high density after mixing with recycled polyethylene, the integral value of the region where the Log Mw is 5.5 or more may be 6% or more, or 8% or more, or 10% or more, or 11.0% or more.

[0091]

[0092] By having an integral value in the region where the Log Mw is 5.5 or more as described above, the ratio of the polymer region in the molecular structure of virgin polyethylene can be strengthened, and mechanical properties such as environmental stress cracking resistance (ESCR) can be improved along with excellent compatibility with recycled polyethylene.

[0093]

[0094] In addition, the new polyethylene has a low molecular weight ratio (LogMw≤4.5 / LogMw≥6.0) obtained from the integral value of the region where the Log MW value is 4.5 or less relative to the total integral value (LogMw≤4.5) based on the integral value of the region where the Log MW value is 6.0 or more relative to the total integral value in a GPC curve graph where the x-axis is log MW and the y-axis is dw / dlogMw, as in Equation 1 below, of 15.5 or more or 15.5 to 50.

[0095] [Formula 1]

[0096] Low molecular weight ratio = LogMw≤4.5 area integral / LogMw≥6.0 area integral.

[0097]

[0098] At this time, the derivation of the low molecular weight content (log Mw≤4.5) and the high molecular weight content (log Mw≥6.0) from the above GPC curve graph represents the percentage value of the area corresponding to each range compared to the total integral value in the GPC curve graph, and the low molecular weight ratio (Log Mw≤4.5 / Log Mw≥6.0) of the above formula 1 according to this is expressed without a separate unit as the ratio of the low molecular weight content to the high molecular weight content described above.

[0099]

[0100] When the low molecular weight ratio (LogMw≤4.5 / LogMw≥6.0) among the molecular structures of the polyethylene satisfies the above-described range, compatibility and processability with recycled polyethylene can be improved.

[0101]

[0102] Specifically, the low molecular weight ratio (LogMw≤4.5 / LogMw≥6.0) of the virgin polyethylene may be 16 or more, or 18 or more, or 20 or more, or 21.5 or more, or 22 or more, or 23.5 or more, or 24 or more, or 24.5 or more, in order to secure excellent processability and compatibility when mixing the polyethylene and recycled polyethylene. However, in order to improve the mechanical properties of the recycled polyethylene, the low molecular weight ratio (LogMw≤4.5 / LogMw≥6.0) of the virgin polyethylene may be 48 or less, or 46 or less, or 45 or less, or 43 or less, or 42 or less, or 40 or less, or 38 or less, or 37.5 or less.

[0103]

[0104] In addition, the polyethylene may satisfy the low molecular weight ratio (LogMw≤4.5 / LogMw≥6.0) range described above, and in a GPC curve graph in which the x-axis is log MW and the y-axis is dw / dlogMw, the integral value (LogMw≥6.0) of an area in which the Log MW value is 6.0 or more relative to the total integral value may be 0.9% or more to 2.2% or less, or 1.0% or more to 2.0% or less, and the integral value (LogMw≤4.5) of an area in which the Log MW value is 4.5 or less relative to the total integral value may be 42% or more to 52% or less, or 44% or more to 50% or less.

[0105]

[0106] In the polyethylene composition of the present invention, the virgin polyethylene has a low molecular weight ratio (LogMw≤4.5 / LogMw≥6.0) as described above, thereby optimizing the low molecular weight region ratio in the molecular structure of the virgin polyethylene, thereby maintaining excellent compatibility with recycled polyethylene and improving mechanical properties such as environmental stress cracking resistance (ESCR).

[0107]

[0108] Meanwhile, the above-mentioned new polyethylene may have an optimized molecular weight distribution (MWD, Mw / Mn) while maintaining a low molecular weight region ratio while strengthening a high molecular weight region ratio within the molecular structure as described above.

[0109]

[0110] Specifically, the new polyethylene may have a molecular weight distribution (Mw / Mn) of 7 or more, or 7 to 18. Preferably, the molecular weight distribution (Mw / Mn) of the polyethylene may be 9 or more, or 10 or more, or 10.5 or more, or 11 or more, or 12 or more, and may also be 17.5 or less, or 17 or less, or 16 or less.

[0111]

[0112] By having the molecular weight distribution (Mw / Mn) as described above, the ratio of high molecular weight regions in the molecular structure of the virgin polyethylene can be strengthened while maintaining the ratio of low molecular weight regions, and excellent compatibility with recycled polyethylene can be maintained, while improving mechanical properties such as environmental stress cracking resistance (ESCR).

[0113]

[0114] For example, the ratio of the area where the Log MW value is 5.0 or more or 4.0 or less and the molecular weight distribution (MWD, polydispersity index) in the above GPC curve graph are measured using gel permeation chromatography (GPC). Specifically, the measurement can be performed using a polystyrene conversion assay using gel permeation chromatography (GPC, gel permeation chromatography, manufactured by Water).

[0115]

[0116] Here, the molecular weight distribution (MWD, polydispersity index) can be calculated by measuring the weight-average molecular weight (Mw) and number-average molecular weight (Mn) of polyethylene and dividing the weight-average molecular weight by the number-average molecular weight.

[0117]

[0118] Specifically, the gel permeation chromatography (GPC) device used is a Waters PL-GPC220 instrument, and a Polymer Laboratories PLgel MIX-B 300 mm long column can be used. The measurement temperature at this time is 160 oC, and 1,2,4-trichlorobenzene can be used as a solvent, and the flow rate can be applied at 1 mL / min. Each of the polyethylene samples was analyzed at 160 in trichlorobenzene (1,2,4-trichlorobenzene) containing 0.0125% butylated hydroxytoluene (BHT) using a GPC analysis instrument (PL-GP220). o C, can be melted and pretreated for 10 hours, prepared at a concentration of 10 mg / 10 mL, and supplied in an amount of 200 microliters (μL). The values ​​of Mw and Mn can be derived using a calibration curve formed using polystyrene standard specimens. The weight-average molecular weight of the polystyrene standard specimens can be used in 9 types: 2000 g / mol, 10000 g / mol, 30000 g / mol, 70000 g / mol, 200000 g / mol, 700000 g / mol, 2000000 g / mol, 4000000 g / mol, and 10000000 g / mol.

[0119]

[0120] In addition, the new polyethylene may have a weight average molecular weight of 100,000 g / mol to 500,000 g / mol. Preferably, the weight average molecular weight of the polyethylene may be 105,000 g / mol or more, or 110,000 g / mol or more, or 115,000 g / mol or more, or 120,000 g / mol or more, or 122,000 g / mol or more, or 125,000 g / mol or more. However, when compatibility with recycled polyethylene is taken into consideration, the weight average molecular weight may be 480,000 g / mol or less, or 450,000 g / mol or less, or 400,000 g / mol or less, or 350,000 g / mol or less, or 300,000 g / mol or less, or 250,000 g / mol or less, or 200,000 g / mol or less, or 180,000 g / mol or less, or 150,000 g / mol or less, or 140,000 g / mol or less.

[0121]

[0122] By having the above weight average molecular weight (Mw), the molecular weight distribution of the virgin polyethylene can be optimized, and mechanical properties such as environmental stress cracking resistance (ESCR) can be improved along with excellent compatibility with recycled polyethylene.

[0123]

[0124] Meanwhile, the above-mentioned new polyethylene can have its melting index optimized while optimizing the ratio of the polymer region and the molecular weight distribution within the molecular structure as described above.

[0125]

[0126] The above new polyethylene has a melt index (MI) 2.16 , ASTM D 1238, 190 ℃, 2.16 kg) may be 0.1 g / 10 min to 1.0 g / 10 min. Preferably, the melt index (MI) of the polyethylene2.16 , ASTM D 1238, 190 ℃, 2.16kg) is 0.12 g / 10min or more, or 0.15 g / 10min or more, or 0.2 g / 10min or more, or 0.25 g / 10min or more, or 0.3 g / 10min or more, or 0.32 g / 10min or more, or 0.35 g / 10min or more, or 0.4 g / 10min or more, or 0.41 g / 10min or more, and 0.98 g / 10min or less, or 0.95 g / 10min or less, or 0.9 g / 10min or less, or 0.85 g / 10min or less, or 0.8 g / 10min or less, or 0.75 g / 10min or less, or 0.72 g / 10min or less, or 0.7 g / 10min or less, or It may be less than 0.68 g / 10 min. As described above, the melt index (MI) of polyethylene 2.16 ) can optimize the molecular weight distribution of polyethylene and improve mechanical properties such as environmental stress cracking resistance (ESCR) along with excellent compatibility with recycled polyethylene.

[0127]

[0128] By having the melting index as described above, the molecular weight of the virgin polyethylene can be optimized, and mechanical properties such as environmental stress cracking resistance (ESCR) can be improved along with excellent compatibility with recycled polyethylene.

[0129]

[0130] Meanwhile, the new polyethylene may have an SCB ( / 1000TC) per 1,000 carbon atoms measured at 160°C using a GPC (gel permeation chromatography)-FTIR (Fourier Transform Infrared Spectrometer) spectrometer of 3.0 or more. Here, the SCB (Short Chain Branch) content represents the content of branches having 2 to 7 carbon atoms per 1,000 carbon atoms (unit: branches / 1,000C).

[0131]

[0132] Specifically, the SCB (Short Chain Branch) content of the new polyethylene can be measured at 160°C using a PerkinElmer Spectrum 100 FT-IR connected to a high-temperature GPC (PL-GPC220) after pretreating the sample by melting it in 1, 2, 4-Trichlorobenzene containing 0.0125% BHT at 160°C for 10 hours using PL-SP260.

[0133]

[0134] Additionally, the new polyethylene may have a BOCD index (Broad Orthogonal Co-monomer Distribution Index) of 1.60 or more, or 1.60 or more and 2.5 or less.

[0135]

[0136] Specifically, the BOCD index (Broad Orthogonal Co-monomer Distribution Index) of the new polyethylene may be 1.60 or more, as obtained by measuring the SCB (Short Chain branch) content at the left and right boundaries of the middle 60% excluding the left and right ends 20% of the total area in the GPC curve graph of polyethylene, where the x-axis is log Mw and the y-axis is dw / dlogMw, as in Equation 2 below.

[0137] [Formula 2]

[0138] .

[0139]

[0140] At this time, the SCB content on the high molecular weight side and the SCB content on the low molecular weight side mean the SCB content value at logMw corresponding to 20% of the high molecular weight side and low molecular weight side regions, respectively, and in the case of the high molecular weight side log Mw and low molecular weight side log Mw values, they are the logMw values ​​corresponding to 20% of the high molecular weight and low molecular weight regions, respectively, compared to the total area of ​​the y-axis (dw / dlogMw) and x-axis (logMw) curves through GPC analysis.

[0141]

[0142] In the present invention, the virgin polyethylene is a semi-crystalline polymer and may include a crystalline portion and an amorphous portion. Specifically, the crystalline portion may include a lamellar crystal including an ethylene repeating unit or an alpha-olefin repeating unit. More specifically, the polymer chain including the ethylene repeating unit or the alpha-olefin repeating unit folds to form a bundle, thereby forming a crystalline block (or segment) in a lamellar shape. The lamellar crystal refers to such a crystalline block in a lamellar shape, and the mechanical properties of the virgin polyethylene may be realized through such a lamellar crystal.

[0143]

[0144] The above ethylene repeating unit refers to a repeating unit included in a homopolymer of an ethylene monomer, and the above alpha-olefin repeating unit may refer to a repeating unit included in a homopolymer of an alpha-olefin monomer. Specific examples of the above alpha-olefin monomer are as described above.

[0145]

[0146] Meanwhile, a plurality of the lamellar crystals can gather together to form a three-dimensionally grown spherulite, and at this time, the portion outside the lamellar crystals corresponds to an amorphous portion. This amorphous portion plays a role in mediating the bonding between the lamellar crystals in the new polyethylene that has formed the spherules. The elastic properties of the new polyethylene can be realized by this amorphous portion. In particular, as the connection between the lamellar crystals becomes stronger, the entire crystal is well bound, and thus the physical properties of the new polyethylene, such as the environmental stress cracking resistance, can be improved.

[0147]

[0148] In particular, the new polyethylene of the present invention has the characteristic of excellent environmental stress cracking resistance due to a high lamellar region area.

[0149]

[0150] Here, the lamellar region area represents the surface area of ​​the lamellar structure in the new polyethylene crystal structure, and the higher the lamellar crystal surface area, the more the portion connecting the crystal structure increases, so it has the characteristic of excellent crack resistance.

[0151]

[0152] Meanwhile, the above-mentioned new polyethylene has a lamellar region area of ​​710 × 10 obtained from Equation 3 below. 10 cm 2 / mol or more or 710 × 10 10 cm 2 / mol or more to 1150 × 10 10 cm 2 / mol or less.

[0153] [Formula 3]

[0154] Lamellar region area (cm) 2 / mol) = (V specific / Lw) × Mw × Tc

[0155] In the above equation 3,

[0156] V specific is the specific volume of polyethylene (cm 3 / g), and

[0157] Mw is the weight average molecular weight (g / mol) of polyethylene measured using gel permeation chromatography (GPC).

[0158] Tc is the crystallinity (%) of polyethylene measured using differential scanning calorimetry (DSC),

[0159] Lw is the thickness (cm) of the lamellar crystal structure of polyethylene measured using differential scanning calorimetry (DSC).

[0160]

[0161] Specifically, the crystal volume of the polyethylene (V specific , Specific volume) is 1 cm as a literature value. 3 / g. In addition, the weight average molecular weight (Mw) of the polyethylene may be a value measured by a polystyrene conversion assay using gel permeation chromatography (GPC, gel permeation chromatography, manufactured by Water Co.) as described above. In addition, the crystallinity (Tc) of the polyethylene may be a value (%) measured based on the melting enthalpy through DSC analysis under the heating / cooling rate of 10 ℃ / min in the range of -50 ℃ or more to 200 ℃ or less. In addition, the lamellar crystal structure thickness (Lw) of the polyethylene is a value (cm) measured based on the SSA experiment using DSC equipment. For example, the SSA experiment is performed by completely melting the polymer, cooling it to the melting point (Tm), offset +5 ℃, and then annealing it while cooling it to Tm onset -5 ℃, and then 2 nd It may be a value calculated by heating and measuring the thickness of the lamellar crystal structure (Lw, Weight-average).

[0162]

[0163] Preferably, the lamellar region area of ​​the new polyethylene is 712 × 10 10 cm 2 / mol or more, or 715 × 10 10 cm 2 / mol or more, or 720 × 10 10 cm 2 / mol can be more than that.

[0164]

[0165] Meanwhile, in the polyethylene composition according to one embodiment of the present invention, the new polyethylene described above may be manufactured using various catalysts, and preferably may be manufactured using a catalyst composition including a metallocene compound, but is not limited thereto.

[0166]

[0167] For example, the new polyethylene may be manufactured by introducing hydrogen gas in the presence of a catalyst composition including a first metallocene compound represented by the following chemical formula 1 and a second metallocene compound represented by the following chemical formula 2.

[0168] [Chemical Formula 1]

[0169] (Cp 1 R a ) n (Cp 2 R b )M 1 Z 1 3-n

[0170] In the above chemical formula 1,

[0171] M 1 is a group 4 transition metal;

[0172] Cp 1 and Cp 2 are each cyclopentadienyl, and these are C 1-20 Substituted or unsubstituted with hydrocarbons;

[0173] R a and R b are identical or different from each other, and each independently represents hydrogen, C 1-20 Alkyl, C 1-20 Alkoxy, C 2-20 Alkoxyalkyl, C 6-20 Aryl, C 6-20 Aryloxy, C 2-20 Alkenyl, C 7-40 Alkylaryl of C 7-40 Arylalkyl of C 8-40 Arylalkenyl, C 2-20C containing one or more heteroatoms selected from the group consisting of alkynyl, or N, O and S 2-20 It is heteroaryl;

[0174] Z 1 Silver halogen, C 1-20 Alkyl, C 2-20 Alkenyl, C 7-40 Alkylaryl, C 7-40 Arylalkyl, C 6-20 Aryl, substituted or unsubstituted C 1-20 Alkylidene, substituted or unsubstituted amino group, C 2-20 Alkylalkoxy, or C 7-40 Aryl alkoxy;

[0175] n is 1 or 0;

[0176] [Chemical Formula 2]

[0177]

[0178] In the above chemical formula 2,

[0179] C1 is any one of the ligands represented by the following chemical formulas 3 to 6,

[0180] [Chemical Formula 3]

[0181]

[0182] [Chemical Formula 4]

[0183]

[0184] [Chemical Formula 5]

[0185]

[0186] [Chemical Formula 6]

[0187]

[0188] In the above chemical formulas 3 to 6,

[0189] R1 to R6 are the same or different and are each independently hydrogen, C 1-30 Alkyl, C 1-30 Alkoxy, C 2-30 Alkoxyalkyl, C 6-30Aryl, C 6-30 Aryloxy, C 2-30 Alkenyl, C 2-30 alkynyl, C 3-30 Cycloalkyl, C 7-40 Alkylaryl of C 8-40 Alkenylaryl, C 8-40 Alkynylaryl, C 7-40 Arylalkyl of C 8-40 Arylalkenyl of, or C 8-40 is arylalkynyl,

[0190] M is Ti, Zr or Hf,

[0191] Z is -O-, -S-, -NR7-, or -PR7-,

[0192] R7 is hydrogen, C 1-30 Alkyl, C 6-30 Aryl, C 2-30 Alkenyl, C 2-30 alkynyl, C 3-30 Cycloalkyl, C 7-40 Alkylaryl of C 8-40 Alkenylaryl, C 8-40 Alkynylaryl, C 7-40 Arylalkyl of C 8-40 Arylalkenyl, C 8-40 Arylalkynyl, C 1-30 Alkoxysilyl group, C 6-30 Aryloxysilyl, C 1-30 Alkylsilyl group, or C 1-30 It is a silylalkyl group,

[0193] X1 and X2 are the same or different and each independently represent halogen, C 1-30 Alkyl, C 2-30 Alkenyl, C 7-30 Alkylaryl, C 7-30 Arylalkyl, C 6-20 Aryl, substituted or unsubstituted C 1-30 Alkylidene, substituted or unsubstituted amino group, C 2-30 Alkylalkoxy, or C 7-30 It is arylalkoxy,

[0194] T is or And,

[0195] T1 is C, Si, Ge, Sn or Pb,

[0196] Y1 is hydrogen, hydrogen, C 1-30 Alkyl, C 1-30 Alkoxy, C 2-30 Alkoxyalkyl, C 6-30 Aryl, C 6-30 Aryloxy, C 2-30 Alkenyl, C 2-30 alkynyl, C 3-30 Cycloalkyl, C 7-40 Alkylaryl of C 8-40 Alkenylaryl, C 8-40 Alkynylaryl, C 7-40 Arylalkyl of C 8-40 Arylalkenyl of, or C 8-40 Aryl alkynyl, silyl group (-SiH3), C 1-30 Alkoxysilyl group, C 2-30 Alkoxyalkylsilyl group, C 6-30 Aryloxysilyl, C 1-30 Haloalkyl, C 6-30 Haloaryl, or -NR9R 10 And,

[0197] Y2 is C 2-30 Alkoxyalkyl, or C 7-40 Aryloxyalkyl,

[0198] R9 and R 10 are each independently hydrogen, C 1-30 Alkyl, C 6-30 Aryl, C 2-30 Alkenyl, C 2-30 alkynyl, C 3-30 Cycloalkyl, C 7-40 Alkylaryl of C 8-40 Alkenylaryl, C 8-40 Alkynylaryl, C 7-40 Arylalkyl of C 8-40 Arylalkenyl of, or C 8-40 arylalkynyl, or are linked to each other to form an aliphatic or aromatic ring.

[0199]

[0200] Meanwhile, in this specification, unless otherwise specifically limited, the following terms may be defined as follows:

[0201]

[0202] The halogen can be fluorine (F), chlorine (Cl), bromine (Br), or iodine (I).

[0203]

[0204] C 1-30 The alkyl group may be a straight-chain, branched-chain or cyclic alkyl group. Specifically, C 1-20 The alkyl group is C 1-15 Straight-chain alkyl group; C 1-10 Straight-chain alkyl group; C 1-5 Straight-chain alkyl group; C 3-20 Branched or cyclic alkyl group; C 3-15 Branched or cyclic alkyl group; or C 3-10 It may be a branched or cyclic alkyl group. More specifically, the C1-20 alkyl group may be a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, an iso-butyl group, a tert-butyl group, an n-pentyl group, an iso-pentyl group, a neo-pentyl group, or a cyclohexyl group.

[0205]

[0206] C 2-30 The alkenyl group may be a straight-chain, branched-chain, or cyclic alkenyl group. Specifically, C 2-30 The alkenyl group is C 2-20 Straight-chain alkenyl group, C 2-10 Straight-chain alkenyl group, C 2-5 Straight-chain alkenyl group, C 3-20 Branched-chain alkenyl group, C 3-15 Branched-chain alkenyl group, C 3-10 Branched-chain alkenyl group, C 5-20 Cyclic alkenyl group or C 5-10 It may be a cyclic alkenyl group. More specifically, C 2-20 The alkenyl group may be an ethenyl group, a propenyl group, a butenyl group, a pentenyl group, or a cyclohexenyl group.

[0207]

[0208] C 6-30 Aryl can mean a monocyclic, bicyclic, or tricyclic aromatic hydrocarbon. Specifically, C 6-30 Aryl can be a phenyl group, a naphthyl group, or anthracenyl group.

[0209]

[0210] C 7-40 Alkylaryl may refer to a substituent in which one or more hydrogens of aryl are replaced by alkyl. Specifically, C 7-40 The alkylaryl may be methylphenyl, ethylphenyl, n-propylphenyl, iso-propylphenyl, n-butylphenyl, iso-butylphenyl, tert-butylphenyl or cyclohexylphenyl.

[0211]

[0212] C 7-40 Arylalkyl may refer to a substituent in which one or more hydrogens of alkyl are replaced by aryl. Specifically, C 7-40 Arylalkyl can be benzyl, phenylpropyl or phenylhexyl.

[0213]

[0214] C above 1-20 Examples of alkoxy groups include, but are not limited to, methoxy, ethoxy, phenyloxy, and cyclohexyloxy.

[0215]

[0216] C above 2-20 An alkoxyalkyl group is a functional group in which at least one hydrogen atom of an alkyl group as described above is replaced with an alkoxy group, and specifically, examples thereof include, but are not limited to, an alkoxyalkyl group such as a methoxymethyl group, a methoxyethyl group, an ethoxymethyl group, an iso-propoxymethyl group, an iso-propoxyethyl group, an iso-propoxyhexyl group, a tert-butoxymethyl group, a tert-butoxyethyl group, and a tert-butoxyhexyl group; or an aryloxyalkyl group such as a phenoxyhexyl group.

[0217]

[0218] C above 1-20Alkylsilyl group or C 1-20 The alkoxysilyl group is a functional group in which 1 to 3 hydrogens of -SiH3 are replaced by 1 to 3 alkyl groups or alkoxy groups as described above, and specifically, examples thereof include, but are not limited to, alkylsilyl groups such as methylsilyl, dimethylsilyl, trimethylsilyl, dimethylethylsilyl, diethylmethylsilyl, or dimethylpropylsilyl; alkoxysilyl groups such as methoxysilyl, dimethoxysilyl, trimethoxysilyl, or dimethoxyethoxysilyl; and alkoxyalkylsilyl groups such as methoxydimethylsilyl, diethoxymethylsilyl, or dimethoxypropylsilyl.

[0219]

[0220] C above 1-20 A silylalkyl group is a functional group in which one or more hydrogens of the alkyl group described above are replaced with a silyl group, and specifically, examples thereof include, but are not limited to, -CH2-SiH3, a methylsilylmethyl group, or a dimethylethoxysilylpropyl group.

[0221]

[0222] The above sulfonate group has the structure -O-SO2-R', where R' is C 1-20 It can be an alkyl group. Specifically, C 1-20 Sulfonate groups include, but are not limited to, methanesulfonate groups or phenylsulfonate groups.

[0223]

[0224] The above heteroaryl is C containing at least one of N, O, and S as a heteroatom. 2-20As heteroaryl, specific examples include xanthene, thioxanthen, thiophene group, furan group, pyrrole group, imidazole group, thiazole group, oxazole group, oxadiazole group, triazole group, pyridyl group, bipyridyl group, pyrimidyl group, triazine group, acridyl group, pyridazine group, pyrazinyl group, quinolinyl group, quinazoline group, quinoxalinyl group, phthalazinyl group, pyrido pyrimidinyl group, pyrido pyrazinyl group, pyrazino pyrazinyl group, isoquinoline group, indole group, carbazole group, benzoxazole group, benzimidazole group, benzothiazole group, benzocarbazole group, benzothiophene group, dibenzothiophene group, benzofuranyl group, Examples thereof include, but are not limited to, phenanthroline, isoxazolyl, thiadiazolyl, phenothiazinyl, and dibenzofuranyl groups.

[0225]

[0226] The above-described substituents may be optionally substituted with one or more substituents selected from the group consisting of a hydroxy group; a halogen; an alkyl group or alkenyl group, an aryl group, an alkoxy group; an alkyl group or alkenyl group, an aryl group, an alkoxy group containing one or more heteroatoms of Groups 14 to 16; a silyl group; an alkylsilyl group or an alkoxysilyl group; a phosphine group; a phosphide group; a sulfonate group; and a sulfone group, within a range that exhibits the same or similar effect as the desired effect.

[0227]

[0228] Also, when two adjacent substituents are linked to each other to form an aliphatic or aromatic ring, it means that the atom(s) of the two substituents and the atom(s) to which the two substituents are linked to form a ring. Specifically, -NR9R 10 R9 and R of 10 Examples of these linked to form aliphatic rings include the piperidinyl group, -NR9R 10 R9 and R of 10An example of these interconnected groups forming an aromatic ring is the pyrrolyl group.

[0229]

[0230] Also, group 4 transition metals include, but are not limited to, titanium (Ti), zirconium (Zr), and hafnium (Hf).

[0231]

[0232] For example, the first metallocene compound represented by the above chemical formula 1 is Cp 1 and Cp 2 As a non-bridged compound containing a ligand of Cp 1 and Cp 2 The ligands may be the same or different, each being cyclopentadienyl, and C 1-10 It may be substituted with one or more alkyl groups or with one to three alkyl groups.

[0233]

[0234] Also, the above Cp 1 and Cp 2 The ligand of Cp can easily control the chemical structure, molecular weight, molecular weight distribution, mechanical properties, transparency, etc. of the olefin polymer produced by controlling the degree of steric hindrance effect depending on the type of substituted functional group, for example. Specifically, the Cp 1 and Cp 2 The ligands of each R a and R b is replaced by , and at this time, the R a and R b are identical or different from each other, and each independently represents hydrogen, C 1-20 Alkyl, C 2-20 Alkoxyalkyl, C 7-40 C containing one or more heteroatoms selected from the group consisting of arylalkyl, or N, O and S 2-12 It may be heteroaryl, more specifically C 1-10 Alkyl, C 2-10 Alkoxyalkyl, C 7-20C containing one or more heteroatoms selected from the group consisting of arylalkyl, or N, O and S 4-12 Heteroaryl; may be.

[0235]

[0236] Also, the above Cp 1 and Cp 2 There is a M between the ligands of 1 Z 1 3-n This exists, M 1 Z 1 3-n can affect the storage stability of metal complexes. To ensure this effect more effectively, Z 1 are each independently halogen or C 1-20 It may be an alkyl, and more specifically, each independently may be F, Cl, Br or I. Also, the above M 1 may be Ti, Zr or Hf; may be Zr or Hf; or may be Zr.

[0237]

[0238] Among the first transition metal compounds, Cp in the chemical formula 1 1 and Cp 2 are each an unsubstituted or substituted cyclopentadienyl group, and R a and R b Each independently hydrogen, C 1-10 Alkyl, C 2-10 Alkoxyalkyl, or C 7-20 Arylalkyl of R a and R b At least one of the compounds may be a substituent of an alkoxyalkyl group such as a t-butoxyhexyl group, more specifically -(CH2)n-OR (wherein R is a straight or branched alkyl group having 1 to 6 carbon atoms, and n is an integer of 2 to 4).

[0239]

[0240] The first metallocene compound represented by the above chemical formula 1 may be, for example, a compound represented by one of the structural formulas below, but is not limited thereto.

[0241] .

[0242]

[0243] In addition, the second metallocene compound includes an aromatic ring compound containing thiophene as a different ligand and a base compound containing a group 14 or 15 atom, and the different ligands are bridged by -T- and have a structure in which M(X1)(X2) exists between the different ligands.

[0244]

[0245] More specifically, in the above chemical formula 2, M may be Ti, Zr or Hf, and more specifically, Ti.

[0246]

[0247] Also, R1 to R4 are each independently hydrogen, or C 1-20 It is alkyl, and more specifically, it can be hydrogen or methyl.

[0248]

[0249] Also, R5 and R6 are each independently C 1-10 is alkyl, and more specifically, both R5 and R6 can be methyl.

[0250]

[0251] Also, Z is -NR7-, and the above R7 is C 1-10 C, such as alkyl, more specifically t-butyl 3-10 It may be a branched alkyl.

[0252]

[0253] Also, T is , and the above T1 is C or Si, and Y1 is C 1-20 Alkyl, C 1-20 Alkoxy, C 2-20 Alkoxyalkyl, C6-20 Aryl, C 7-30 Alkylaryl, C 7-30 Arylalkyl, C 6-20 Aryloxy, or C 7-30 Aryloxyalkyl, and Y2 is C 2-20 Alkoxyalkyl, or C 7-30 Aryloxyalkyl, and more specifically, Y1 can be any one of a methyl group, an ethyl group, an n-propyl group and an n-butyl group, and Y2 is C 2-20 Alkoxyalkyl, or C 7-30 Aryloxyalkyl, and more specifically, Y2 may be any one of a methoxymethyl group, a methoxyethyl group, an ethoxymethyl group, an iso-propoxymethyl group, an iso-propoxyethyl group, an iso-propoxyhexyl group, a tert-butoxymethyl group, a tert-butoxyethyl group, a tert-butoxyhexyl group, and a phenoxyhexyl group.

[0254]

[0255] Also, X1 and X2 are each independently halogen or C 1-20 It may be alkyl, or more specifically chloro.

[0256]

[0257] As an example, as the second metallocene compound, compounds represented by the following chemical formulas 2a to 2d can be exemplified.

[0258] [Chemical Formula 2a]

[0259]

[0260] [Chemical Formula 2b]

[0261]

[0262] [Chemical Formula 2c]

[0263]

[0264] [Chemical formula 2d]

[0265]

[0266] In the above chemical formulas 2a to 2d, R1 to R7, M, X1, X2, T1, Y1 and Y2 are as defined above.

[0267]

[0268] More specifically, the second metallocene compound is, in the chemical formulas 2a to 2d, M is Ti, Zr or Hf, more specifically Ti; R1 to R4 are each independently hydrogen, or C 1-20 alkyl, more specifically hydrogen or methyl; R5 and R6 are each independently C 1-10 is alkyl, and more specifically, both R5 and R6 are methyl; wherein R7 is C 1-10 Alkyl, more specifically C, such as t-butyl 3-10 Branched alkyl; wherein T1 is C or Si, and Y1 is C 1-20 Alkyl, C 1-20 Alkoxy, C 2-20 Alkoxyalkyl, C 6-20 Aryl, C 7-30 Alkylaryl, C 7-30 Arylalkyl, C 6-20 Aryloxy, or C 7-30 Aryloxyalkyl, and Y2 is C 2-20 Alkoxyalkyl, or C 7-30 Aryloxyalkyl, more specifically, Y1 is any one of a methyl group, an ethyl group, an n-propyl group and an n-butyl group, and Y2 is C 2-20 Alkoxyalkyl, or C 7-30 Aryloxyalkyl, more specifically, Y2 is any one of a methoxymethyl group, a methoxyethyl group, an ethoxymethyl group, an iso-propoxymethyl group, an iso-propoxyethyl group, an iso-propoxyhexyl group, a tert-butoxymethyl group, a tert-butoxyethyl group, a tert-butoxyhexyl group and a phenoxyhexyl group, and X1 and X2 are each independently halogen or C 1-20 It may be an alkyl compound, more specifically a chloro compound.

[0269]

[0270] More specifically, specific examples of the second metallocene compound include, but are not limited to, compounds having the following structures:

[0271] .

[0272]

[0273] In addition, the content ratio of the first and second metallocene compounds in the catalyst composition may be included in a molar ratio of 1:1.1 to 1:5, and more specifically, may be 1:1.1 or more, or 1:1.2 or more, or 1:1.3 or more, and 1:5 or less, or 1:3 or less.

[0274]

[0275] Meanwhile, the catalyst composition may further include a carrier, in which case the first and second metallocene compounds are used in a state supported on the carrier.

[0276]

[0277] Specific examples of the above carriers include silica, alumina, magnesia, silica-alumina, silica-magnesia, etc., and these may further include oxide, carbonate, sulfate, and nitrate components, such as Na2O, K2CO3, BaSO4, and Mg(NO3)2.

[0278]

[0279] In addition, the catalyst composition may additionally include a cocatalyst to improve high activity and process stability, and the cocatalyst may be, more specifically, an alkylaluminoxane-based cocatalyst such as methylaluminoxane, ethylaluminoxane, isobutylaluminoxane, or butylaluminoxane.

[0280]

[0281] Meanwhile, in the polyethylene composition according to one embodiment of the present invention, the virgin polyethylene described above is manufactured by polymerizing ethylene using the catalyst composition described above, and the polymerization process can be performed as a monomodal (or unimodal) polymerization process in which a polymerization reaction is performed under a single polymerization reaction condition using a single catalyst in one reactor, and more specifically, it can be performed in the presence of the hybrid supported catalyst described above in one loop-type slurry reactor.

[0282]

[0283] At this time, the polymerization temperature may be 25°C to 500°C, preferably 25°C to 200°C, and more preferably 50°C to 150°C. In addition, the polymerization pressure may be 1 Kgf / ㎠ to 100 Kgf / ㎠, preferably 1 Kgf / ㎠ to 50 Kgf / ㎠, and more preferably 5 Kgf / ㎠ to 30 Kgf / ㎠.

[0284]

[0285] Meanwhile, according to the present invention, the polyethylene composition includes recycled polyethylene (PCW PE, Post consumer waste polyethylene) together with the virgin polyethylene described above.

[0286]

[0287] Specifically, the polyethylene composition of the present invention may contain 10 wt% to 90 wt% of recycled polyethylene (PCW PE). In particular, in order to enhance the carbon dioxide emission suppression effect of the polyethylene composition and reduce costs, the content of the recycled polyethylene (PCW PE) may be 20 wt% or more, or 30 wt% or more, or 35 wt% or more, or 40 wt% or more, or 45 wt% or more, or 50 wt% or more, or 55 wt% or more. In addition, in order to enhance the mechanical properties of the polyethylene composition, such as impact strength, tensile strength, chemical resistance, and thermal stability, and to minimize the virgin resin content, the content of the recycled polyethylene (PCW PE) may be 85 wt% or less, or 80 wt% or less, or 75 wt% or less, or 70 wt% or less, or 65 wt% or less, or 60 wt% or less.

[0288]

[0289] The above recycled polyethylene (PCW PE) has a melt index (MI) 2.16 , 190 o C, measured under a load of 2.16 kg) may be 0.10 g / 10 min to 0.3 g / 10 min, specifically 0.12 g / 10 min to 0.28 g / 10 min, or 0.13 g / 10 min to 0.25 g / 10 min, or 0.15 g / 10 min to 0.2 g / 10 min.

[0290]

[0291] In addition, the above recycled polyethylene (PCW PE) has a density of 0.951 g / cm 3 0.953 g / cm 3 It can be expressed as a characteristic of a person.

[0292]

[0293] Additionally, the recycled polyethylene (PCW PE) may have an environmental stress cracking resistance (ESCR) of 40 to 50 hours as measured according to ASTM D 1693 (Condition B, F50, Igepal 10%).

[0294]

[0295] The polyethylene composition according to the present invention uses recycled polyethylene together with virgin polyethylene as described above, optimizes density and complex viscosity (η*(ω500), complex viscosity), and increases environmental stress cracking resistance (ESCR), thereby enabling the production of a molded product having high mechanical properties along with excellent processability.

[0296]

[0297] In particular, the polyethylene composition according to the present invention can secure excellent impact strength, tensile strength, chemical resistance, and thermal stability close to those of virgin resin while increasing the content of recycled polyethylene.

[0298]

[0299] Specifically, the polyethylene composition is manufactured by using an injection molding machine to make a disk specimen having a diameter of 50 mm and a thickness of 2 mm, and a weight is fixed on the disk specimen with a drop energy of 4.2 J, and the number of drops until a crack occurs is measured, and the drop impact strength can be 7 or more.

[0300]

[0301] In addition, the polyethylene composition has a flexural modulus of 13000 kgf / cm as measured by the ASTM D 790 method. 2 or more than 13500 kgf / cm 2 Up to 14800 kgf / cm 2It can be. Preferably, the flexural modulus of the polyethylene composition is 13100 kgf / cm in terms of implementing excellent mechanical properties and impact strength when used as a blow container. 2 or 13200 kgf / cm 2 or 13300 kgf / cm 2 or 13400 kgf / cm 2 or 13500 kgf / cm 2 It may be ideal. However, in terms of securing excellent processability when using the polyethylene composition as a blow container, the flexural modulus is 14700 kgf / cm 2 or less, or 14600 kgf / cm 2 or less, or 14500 kgf / cm 2 or less, or 14300 kgf / cm 2 or less, or 14000 kgf / cm 2 or less, or 13900 kgf / cm 2 or less, or 13800 kgf / cm 2 or less, or 13700 kgf / cm 2 or less, or 13600 kgf / cm 2 It could be as follows:

[0302]

[0303] Hereinafter, preferred examples are presented to aid in understanding the present invention. However, the following examples are provided solely to facilitate a better understanding of the present invention and are not intended to limit the scope of the present invention.

[0304]

[0305] <Example>

[0306] Example 1: Preparation of polyethylene composition

[0307] A polyethylene composition (PCR Compound) was manufactured by dry blending 50 wt% of virgin polyethylene and 50 wt% of recycled polyethylene (PCW PE, Post consumer waste polyethylene), and then extruding through a twin screw extruder.

[0308]

[0309] The recycled polyethylene used at this time (Baeksan Natural product of Baeksan Plastic Co., Ltd.) has a melting index of MI 2.16 (190 according to ASTM D 1238 (Condition E) o (measured under 2.16 kg load under C) is 0.15 g / 10 min to 0.2 g / 10 min, and the density (measured according to ASTM D 1505 standard) is 0.951 g / cm 3 0.953 g / cm 3 , ESCR (time to F50 (50% destruction) measured under temperature conditions of 50℃ using 10% Igepal CO-630 Solution according to ASTM D 1693) is at the level of 40 to 50 hours.

[0310]

[0311] In addition, the virgin polyethylene used at this time was produced by injecting 15 kg / h of isobutane and 33 kg / h of ethylene in a single slurry loop reactor in the presence of a catalyst (molar ratio of the first metallocene compound and the second metallocene compound = 1:1.3) in which the first metallocene compound (1) and the second metallocene compound (2) are hybrid-supported on a silica carrier (Grace Davison, SP2212), and performing a copolymerization process with 195 ppm and 200 ppm of hydrogen, and 0.8 wt% and 2.2 wt% of comonomer (1-hexene), respectively, and then passing through a solvent removal facility and a dryer, dry blending the obtained high-density ethylene / 1-hexene copolymer in powder form to produce high-density virgin polyethylene (HDPE, Virgin polyethylene). The specific physical properties of the virgin polyethylene produced in this way are shown in Table 1 below.

[0312] (1) (2)

[0313]

[0314] Example 2: Preparation of polyethylene composition

[0315] A polyethylene composition (PCR Compound) was prepared in the same manner as in Example 1, but a polyethylene resin having the properties shown in Table 1 below was used as virgin polyethylene together with the above-described recycled polyethylene (Baeksan Natural product of Baeksan Plastic Co., Ltd.), to prepare a polyethylene composition of Example 2.

[0316]

[0317] At this time, the virgin polyethylene used was manufactured in the same manner as in Example 1, but was changed to 230 ppm of hydrogen and 2.0 wt% of Comonomer (1-hexene) and homopolymerized to manufacture high-density virgin polyethylene (HDPE, Virgin polyethylene) in powder form.

[0318]

[0319] Example 3: Preparation of polyethylene composition

[0320] A polyethylene composition (PCR Compound) was prepared in the same manner as in Example 1, but a polyethylene resin having the properties shown in Table 1 below was used as virgin polyethylene together with the above-described recycled polyethylene (Baeksan Natural product of Baeksan Plastic Co., Ltd.), thereby preparing a polyethylene composition of Example 3.

[0321]

[0322] At this time, the new polyethylene used was manufactured in the same manner as Example 1, but changed to 145 ppm of hydrogen and 1.7 wt% of Comonomer (1-hexene) and then homopolymerized to obtain a density of 0.958 g / cm. 3 , melting index (MI) 2.16 ) was dry blended with a high-density polyethylene product (ME9180 product of LG Chem) based on ethylene homopolymer with a yield of 18 g / 10 min to produce a powder-type high-density new polyethylene (HDPE, Virgin polyethylene).

[0323]

[0324] Comparative Example 1: Preparation of polyethylene composition

[0325] A polyethylene composition (PCR Compound) was prepared in the same manner as in Example 1, but a polyethylene resin having the properties shown in Table 2 below was used as virgin polyethylene together with the above-described recycled polyethylene (Baeksan Natural product of Baeksan Plastic Co., Ltd.), thereby preparing a polyethylene composition of Comparative Example 1.

[0326]

[0327] At this time, the virgin polyethylene used was manufactured in the same manner as in Example 1, but was changed to 222 ppm of hydrogen and 0.8 wt% of Comonomer (1-hexene) and homopolymerized to manufacture high-density virgin polyethylene (HDPE, Virgin polyethylene) in powder form.

[0328]

[0329] Comparative Example 2: Preparation of polyethylene composition

[0330] A polyethylene composition (PCR Compound) was prepared in the same manner as in Example 1, but a polyethylene resin having the properties shown in Table 2 below was used as virgin polyethylene together with the above-described recycled polyethylene (Baeksan Plastic, Baeksan Natural), thereby preparing a polyethylene composition of Comparative Example 2.

[0331]

[0332] At this time, the virgin polyethylene used was manufactured in the same manner as in Example 1, but was changed to 145 ppm of hydrogen and 1.7 wt% of Comonomer (1-hexene) and homopolymerized to manufacture high-density virgin polyethylene (HDPE, Virgin polyethylene) in powder form.

[0333]

[0334] Comparative Example 3: Preparation of polyethylene composition

[0335] A polyethylene composition (PCR Compound) was prepared in the same manner as in Example 1, but a polyethylene resin having the properties shown in Table 2 below was used as virgin polyethylene together with the above-described recycled polyethylene (Baeksan Natural product of Baeksan Plastic Co., Ltd.), to prepare a polyethylene composition of Comparative Example 3.

[0336]

[0337] At this time, the new polyethylene used was manufactured in the same manner as Example 1, but changed to 222 ppm of hydrogen and 0.8 wt% of Comonomer (1-hexene) and then homopolymerized to obtain a density of 0.957 g / cm. 3 , melting index (MI) 2.16 ) High-density polyethylene product (ME8000 product of LG Chem) with 8 g / 10 min was dry blended to produce high-density new polyethylene (HDPE, Virgin polyethylene) in powder form.

[0338]

[0339] Comparative Example 4: Preparation of polyethylene composition

[0340] A polyethylene composition (PCR Compound) was prepared in the same manner as in Example 1, but a polyethylene resin having the properties shown in Table 2 below was used as virgin polyethylene together with the above-described recycled polyethylene (Baeksan Natural product of Baeksan Plastic Co., Ltd.), to prepare a polyethylene composition of Comparative Example 4.

[0341]

[0342] At this time, the new polyethylene used had a density of 0.941 g / cm 3 , melting index (MI) 2.16 ) High-density polyethylene product based on ethylene / 1-hexene copolymer with a density of 0.6 g / 10 min (SP988 product from LG Chem) and a density of 0.961 g / cm3 , melting index (MI) 2.16 ) 5.5 g / 10 min ethylene homopolymer-based high-density polyethylene product (ME6000 product of LG Chem) was dry blended to produce high-density new polyethylene (HDPE, Virgin polyethylene) in powder form.

[0343]

[0344] Comparative Example 5: Preparation of polyethylene composition

[0345] A polyethylene composition (PCR Compound) was prepared in the same manner as in Example 1, but a polyethylene resin having the properties shown in Table 2 below was used as virgin polyethylene together with the above-described recycled polyethylene (Baeksan Natural product of Baeksan Plastic Co., Ltd.), to prepare a polyethylene composition of Comparative Example 5.

[0346]

[0347] At this time, the new polyethylene used was manufactured in the same manner as Example 1, but changed to 240 ppm of hydrogen and 2.9 wt% of Comonomer (1-hexene) and then homopolymerized to obtain a density of 0.941 g / cm. 3 , melting index (MI) 2.16 ) High-density polyethylene product (LG Chem's SP988 product) with 0.6 g / 10 min was dry blended to produce high-density new polyethylene (HDPE, Virgin polyethylene) in powder form.

[0348]

[0349] Comparative Example 6: Preparation of polyethylene composition

[0350] A polyethylene composition (PCR Compound) was prepared in the same manner as in Example 1, but a polyethylene resin having the properties shown in Table 2 below was used as virgin polyethylene together with the above-described recycled polyethylene (Baeksan Natural product of Baeksan Plastic Co., Ltd.), to prepare a polyethylene composition of Comparative Example 6.

[0351]

[0352] At this time, the virgin polyethylene used was manufactured in the same manner as in Example 1, but the hydrogen was changed to 240 ppm and 222 ppm, and the comonomer (1-hexene) to 2.9 wt% and 0.8 wt%, respectively, and the copolymerization process was performed. Then, the obtained powdered ethylene / 1-hexene copolymer was dry blended to manufacture high-density virgin polyethylene (HDPE, Virgin polyethylene) in powder form.

[0353]

[0354] <Example of an exam>

[0355] The physical properties of virgin polyethylene (HDPE, Virgin polyethylene) used in the examples and comparative examples and the polyethylene composition (PCR Compound) manufactured thereby were evaluated using the following method, and the measurement results are shown in Tables 1 and 2 below, respectively.

[0356]

[0357] (1) Density

[0358] Density (g / cm) of virgin polyethylene (HDPE) and polyethylene composition (PCR Compound) according to ASTM D 1505 standard of the American Society for Testing and Materials 3 ) was measured.

[0359]

[0360] (2) Weight average molecular weight and molecular weight distribution (PDI, polydispersity index, Mw / Mn) and Log MW (5.5 or higher and low molecular weight) ratio according to GPC analysis

[0361] For virgin polyethylene (HDPE), the weight-average molecular weight (Mw) and number-average molecular weight (Mn) of the polymer were measured using gel permeation chromatography (GPC, manufactured by Water), and the molecular weight distribution (PDI, Mw / Mn) was calculated by dividing the weight-average molecular weight by the number-average molecular weight.

[0362]

[0363] Specifically, a Waters PL-GPC220 gel permeation chromatography (GPC) device was used, and a Polymer Laboratories PLgel MIX-B 300 mm column was used. The measurement temperature was 160°C, 1,2,4-trichlorobenzene was used as a solvent, and the flow rate was 1 mL / min. The polymer samples according to the examples and comparative examples were each pretreated by dissolving in trichlorobenzene (1,2,4-trichlorobenzene) containing 0.0125% butylated hydroxytoluene (BHT) at 160°C for 10 hours using a GPC analysis device (PL-GP220), and then preparing a concentration of 10 mg / 10 mL, and then supplying in an amount of 200 μL. The values ​​of Mw and Mn were derived using a calibration curve formed using polystyrene standard specimens. The weight-average molecular weights of the polystyrene standard specimens were 2000 g / mol, 10000 g / mol, 30000 g / mol, 70000 g / mol, 200000 g / mol, 700000 g / mol, 2000000 g / mol, 4000000 g / mol, and 10000000 g / mol, which were nine types.

[0364]

[0365] In addition, the logarithmic graph for the weight average molecular weight (Mw) of virgin polyethylene (HDPE) measured through GPC analysis, that is, the GPC curve graph in which the x-axis is log MW and the y-axis is dw / dlogMw, the ratio of the integral value of the region in which the Log MW value is 5.5 or more to the total integral value (Log Mw ≥ 5.5, unit: %) was calculated and shown in Tables 1 and 2 below. In addition, in the same manner as above, the integral value of the region in which the Log MW value is 6.0 or more to the total integral value (Log Mw ≥ 6.0, unit: %) and the integral value of the region in which the Log MW value is 4.5 or less (Log Mw ≤ 4.5, unit: %) were obtained, and the low molecular weight ratio was calculated using Equation 1 below and shown in Tables 1 and 2 below.

[0366] [Formula 1]

[0367] Low molecular weight ratio = LogMw≤4.5 area integral / LogMw≥6.0 area integral.

[0368]

[0369] At this time, the derivation of the low molecular weight content (log Mw≤4.5) and high molecular weight content (log Mw≥6.0) from the above GPC curve graph represents the percentage value of the area corresponding to each range compared to the total integral value in the GPC curve graph.

[0370]

[0371] (3) SCB

[0372] SCB ( / 1000TC) was measured for virgin polyethylene (HDPE) at 160 ℃ using GPC-FTIR equipment.

[0373]

[0374] Specifically, the sample was pretreated by dissolving it in 1, 2, 4-Trichlorobenzene containing 0.0125% BHT at 160°C for 10 hours using PL-SP260, and then measured at 160°C using PerkinElmer Spectrum 100 FT-IR connected to high-temperature GPC (PL-GPC220).

[0375]

[0376] (4) BOCD

[0377] As described above, the logarithmic graph of the weight average molecular weight (Mw) of virgin polyethylene (HDPE) measured through GPC analysis, i.e., the GPC curve graph in which the x-axis is log MW and the y-axis is dw / dlogMw, was used to measure the SCB (Short Chain branch) content at the left and right boundaries of the middle 60% excluding the 20% of the left and right ends of the total area, and the BOCD was measured as in Equation 2 below.

[0378] [Formula 2]

[0379] .

[0380] At this time, the SCB content on the high molecular weight side and the SCB content on the low molecular weight side mean the SCB content value at logMw corresponding to 20% of the high molecular weight side and low molecular weight side regions, respectively, and in the case of the high molecular weight side log Mw and low molecular weight side log Mw values, they are the logMw values ​​corresponding to 20% of the high molecular weight and low molecular weight regions, respectively, compared to the total area of ​​the y-axis (dw / dlogMw) and x-axis (logMw) curves through GPC analysis.

[0381]

[0382] (5) Lamellar region

[0383] For virgin polyethylene (HDPE), the lamellar area (×10) is as shown in Equation 3 below. 10 cm 2 / mol) was measured.

[0384] [Formula 3]

[0385] Lamellar region area (cm) 2 / mol) = (V specific / Lw) × Mw × Tc

[0386] In the above equation 3,

[0387] V specific is the specific volume of polyethylene (cm 3 / g), and

[0388] Mw is the weight average molecular weight (g / mol) of polyethylene measured using gel permeation chromatography (GPC).

[0389] Tc is the crystallinity (%) of polyethylene measured using differential scanning calorimetry (DSC),

[0390] Lw is the thickness (cm) of the lamellar crystal structure of polyethylene measured using differential scanning calorimetry (DSC).

[0391]

[0392] Here, the crystal volume of the polyethylene (V specific , Specific volume) is 1 cm as a literature value. 3 / g. In addition, the weight average molecular weight (Mw) of the polyethylene was measured by a polystyrene conversion assay using gel permeation chromatography (GPC, manufactured by Water Co.) as described above. In addition, the crystallinity (Tc) of the polyethylene was measured (%) based on the melting enthalpy through DSC analysis under the heating / cooling rate of 10 ℃ / min in the range of -50 ℃ or more to 200 ℃ or less. In addition, the lamellar crystal structure thickness (Lw) of the polyethylene was measured (cm) based on the SSA experiment using DSC equipment. In this case, the SSA experiment was performed by completely melting the polymer, cooling it to the melting point (Tm), offset +5 ℃, and then annealing it while cooling it to the Tm onset -5 ℃, and then 2 nd This was the value calculated by heating and measuring the thickness of the lamellar crystal structure (Lw, Weight-average).

[0393]

[0394] The values ​​measured in the same manner as described above are 10 10 The area of ​​the lamellar region of the new polyethylene is rounded off to the nearest whole number in Table 1 below (cm). 2 / mol).

[0395]

[0396] (6) Complex Viscosity

[0397] Complex Viscosity (500 rad / s, Pa.s) of polyethylene composition (PCR Compound) was measured at 190 ℃ and 500 rad / s using ARES-G2 equipment.

[0398]

[0399] (7) Drop impact

[0400] A disc was manufactured based on a polyethylene composition (PCR Compound) using the following method, and the number of times a crack occurred in the disc by dropping a weight on the disc was measured, and the number of times the crack occurred in the disc was expressed as the number of drop impacts (times) in Tables 1 and 2 below.

[0401]

[0402] 7-1. Drop Impact Disc Manufacturing

[0403] - The disc was manufactured using an injection molding machine, and was manufactured by injecting PCR Compound after setting the temperature gradient to range from 210℃ to 230℃.

[0404] - Disc size (Φ 50 mm, thickness 2 mm).

[0405]

[0406] 7-2. Drop impact evaluation

[0407] - Using the Instron 9450 (Impact Drop Tower) product, the number of times cracks occur is measured by dropping a weight after fixing the disc (fixing the dropping energy to 4.2 J).

[0408]

[0409] (8) ESCR

[0410] The time to F50 (50% destruction) was measured for a polyethylene composition (PCR Compound) as a compression molded sample having a thickness of 2 mm under Condition B at a temperature of 50°C using 10% Igepal CO-630 Solution according to the method of ASTM D 1693-07, and is shown as ESCR (hr) in Tables 1 and 2 below.

[0411]

[0412] (9) Melt index

[0413] 190 according to the American Society for Testing and Materials standard ASTM D 1238 (Condition E) oMelt index (MI) of virgin polyethylene (HDPE) and polyethylene composition (PCR Compound) under a load of 2.16 kg at C 2.16 ) was measured and expressed as the weight (g) of the polymer melted over 10 minutes.

[0414]

[0415] (10) Flexural modulus

[0416] Flexural modulus (kgf / cm) for polyethylene composition (PCR Compound) according to ASTM D 790 method 2 ) was measured.

[0417]

[0418] Example 1 Example 2 Example 3 New polyethylene (HDPE, Virgin polyethylene) Density (g / cm) 3 )0.9460.9440.945MI 2.16 (g / 10min)0.450.680.41Weight average molecular weight (g / mol)137,800127,400138,300LogMw≥6.0 (%)1.31.41.8LogMw≥5.5 (%)11.811.612.5LogMw≤4.5 (%)48.349.144.7Low molecular weight ratio (%)37.135.424.9SCB ( / 1000TC)4.13.33.1BOCD2.221.931.62Crystallinity (%)71.270.771Lamellar thickness (nm)13.612.313.8Lamellar area (cm) 2 / mol, x10 10 )721732712 Polyethylene composition (PCR Compound, recycled raw material + virgin polyethylene) Density (g / cm 3 )0.9490.9490.949MI 2.16(g / 10min)0.290.380.25Complex Viscosity (500rad / s, Pa.s)516562558Complex Viscosity (0.05rad / s, Pa.s)514673895744508Complex Viscosity (300rad / s, Pa.s)864885855ESCR (hr)285285203Drop impact strength (times)9107Flexural Modulus (kgf / cm 2 )13,50013,40013,600

[0419] Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Polyethylene (HDPE, Virgin polyethylene) Density (g / cm) 3 )0.9470.9430.9480.9440.9430.943MI 2.16 (g / 10min)0.170.210.290.730.540.73Weight average molecular weight (g / mol)202,700170,500167,800120,100125,100120,000LogMw≥6.0 (%)4.22.83.20.91.21.3LogMw≥5.5 (%)18.916.414.78.911.711LogMw≤4.5 (%)39.943.141.231.146.350.3Low molecular weight ratio (%)9.415.212.836.137.139SCB ( / 1000TC)2.33.41.83.54.85.2BOCD0.91.390.871.532.522.96Crystallization degree71.570.272.270.569.870Lamellar thickness(nm)1311.917.31211.711.5Lamellar area(cm) 2 / mol, x10 10 )11151006699706746730Polyethylene composition (PCR Compound, recycled raw material + virgin polyethylene)Density (g / cm 3 )0.9500.9460.9490.9490.9470.946MI 2.16(g / 10min)0.150.180.210.330.240.33Complex Viscosity (500rad / s, Pa.s)654616571681579543Complex Viscosity (0.05rad / s, Pa.s)476395885057404332293436437338Complex Viscosity (300rad / s, Pa.s)877895932781724753ESCR (hr)45071017090306255Drop impact strength (times)5651299Flexural Modulus (kgf / cm 2 )13,50012,00013,40013,50012,10011,900

[0420]

[0421] Referring to Table 1 above, the polyethylene compositions of Examples 1 to 3 of the present invention have excellent effects of optimizing density and complex viscosity (η*(ω500)) and increasing environmental stress cracking resistance (ESCR), thereby realizing high loading strength with excellent mechanical properties when used as a blow container even though recycled polyethylene (PCW PE) is blended at 50 wt%, while simultaneously securing excellent processability and high drop strength.

[0422]

[0423] On the other hand, referring to Table 2 above, it can be seen that in the case of Comparative Examples 1 to 6, it is not possible to secure mechanical properties capable of realizing high loading strength, excellent processability, and high drop strength at the same time. Specifically, in Comparative Example 1, it can be seen that the LogMw≥5.5 and low molecular weight ratio of virgin polyethylene (HDPE, Virgin polyethylene) decrease, and the viscosity and drop impact of the polyethylene composition (PCR Compound) decrease. In addition, it can be seen that in Comparative Example 2, the density, LogMw≥5.5, and low molecular weight ratio of virgin polyethylene (HDPE, Virgin polyethylene) decrease, and the density, viscosity, and drop impact of the polyethylene composition (PCR Compound) decrease. In Comparative Example 3, it can be seen that the LogMw≥5.5, SCB, BOCD, and lamellar region of virgin polyethylene (HDPE, Virgin polyethylene) decrease, and the drop impact and ESCR of the polyethylene composition (PCR Compound) both decrease. In addition, Comparative Example 4 may have problems such as a decrease in BOCD and lamellar area of ​​virgin polyethylene (HDPE), a decrease in ESCR of polyethylene composition (PCR Compound), and a decrease in long-term physical properties when used as a blow container. Comparative Examples 5 and 6 may have problems such as a decrease in density of virgin polyethylene (HDPE), and a decrease in density of polyethylene composition (PCR Compound), making it difficult to achieve sufficient loading strength when used as a blow container.

Claims

1. A polyethylene composition comprising virgin polyethylene and recycled polyethylene (PCW PE, Post consumer waste polyethylene), The above polyethylene composition satisfies the following (a) to (d): Polyethylene composition: (a) Density 0.949 g / cm 3 more, (b) Melting index (MI) 2.16 , ASTM D 1238, 190 ℃, 2.16kg) 0.25 g / 10min or more, (c) The complex viscosity (η*(ω500), complex viscosity) measured at a frequency (ω) of 500 rad / s is 600 Paㆍs or less, (d) Environmental stress cracking resistance (ESCR) of 200 hours or more as measured according to ASTM D 1693 (Condition B, F50, Igepal 10%).

2. In paragraph 1, The above polyethylene composition has a density of (a) 0.949 g / cm 3 0.954 g / cm 3 person, Polyethylene composition.

3. In paragraph 1, The above polyethylene composition has a melting index (MI) of (b) 2.16 , ASTM D 1238, 190 ℃, 2.16kg) is 0.25 g / 10min to 0.8 g / 10min, Polyethylene composition.

4. In paragraph 1, The above polyethylene composition has a complex viscosity (η*(ω500)) of 500 Paㆍs to 600 Paㆍs. Polyethylene composition.

5. In paragraph 1, The above polyethylene composition has an environmental stress cracking resistance (ESCR) of 200 to 500 hours, Polyethylene composition.

6. In paragraph 1, The above new polyethylene is an ethylene homopolymer or an ethylene / alpha-olefin copolymer. Polyethylene composition.

7. In paragraph 6, The above alpha-olefin is at least one selected from the group consisting of 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, and mixtures thereof. Polyethylene composition.

8. In paragraph 1, The above new polyethylene has a density of 0.944 g / cm 3 Lee Sang-in, Polyethylene composition.

9. In paragraph 1, The above-mentioned new polyethylene is a polyethylene GPC curve graph in which the x-axis is log Mw and the y-axis is dw / dlogMw, in which the integral value of the region in which Log Mw is 5.5 or more is 14% or less of the total integral value. Polyethylene composition.

10. In paragraph 1, The above new polyethylene has a low molecular weight ratio (LogMw≤4.5 / LogMw≥6.0) of 15.5 or more, obtained from the integral value of the region where the Log MW value is 4.5 or less relative to the total integral value (LogMw≥6.0) based on the integral value of the region where the Log MW value is 6.0 or more relative to the total integral value in a GPC curve graph where the x-axis is log MW and the y-axis is dw / dlogMw, as in Equation 1 below. Polyethylene composition: [Formula 1] Low molecular weight ratio = LogMw≤4.5 area integral / LogMw≥6.0 area integral.

11. In paragraph 1, The above new polyethylene has a melt index (MI) measured at 190°C and 2.16 kg load according to ASTM D 1238. 2.16 ) is 0.1 g / 10 min to 1.0 g / 10 min, Polyethylene composition.

12. In paragraph 1, The above new polyethylene has an SCB ( / 1000TC) per 1000 carbon atoms of 3.0 or more as measured at 160°C using a GPC-FTIR spectrometer. Polyethylene composition.

13. In paragraph 1, The above new polyethylene has a BOCD index (Broad Orthogonal Co-monomer Distribution Index) of 1.60 or higher. Polyethylene composition.

14. In paragraph 1, The above new polyethylene has a lamellar area of ​​710 × 10 10 cm 2 / mol or more, Polyethylene composition.

15. In paragraph 1, Containing 10 to 90 wt% of the above recycled polyethylene (PCW PE, Post consumer waste polyethylene), Polyethylene composition.

16. In paragraph 1, The above recycled polyethylene (PCW PE, Post consumer waste polyethylene) has a melt index (MI) measured at 190°C and 2.16 kg load according to ASTM D 1238. 2.16 ) is 0.15 g / 10 min to 0.2 g / 10 min, Polyethylene composition.

17. In paragraph 1, The above recycled polyethylene (PCW PE, Post consumer waste polyethylene) has a density of 0.951 g / cm 3 0.953 g / cm 3 person, Polyethylene composition.

18. In paragraph 1, The above recycled polyethylene (PCW PE, Post consumer waste polyethylene) is a polyethylene composition having an environmental stress cracking resistance (ESCR) of 40 to 50 hours as measured according to ASTM D 1693 (Condition B, F50, Igepal 10%).

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