Polyethylene and film comprising same

Abstract

The present invention provides a polyethylene having excellent low-temperature sealing properties and hot-tack properties, and a film comprising same.

Description

Polyethylene and films containing the same

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

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2024-0073747, filed June 5, 2024, and Korean Patent Application No. 10-2025-0073567, filed June 5, 2025, the entire contents of which are incorporated herein by reference.

[0003] The present invention relates to polyethylene having excellent low-temperature sealing properties and hot-tack properties and a film comprising the same.

[0004]

[0005] Linear low density polyethylene (LLDPE) is a resin manufactured by copolymerizing ethylene and alpha-olefin at low pressure using a polymerization catalyst. It has a narrow molecular weight distribution, short-chain branches of a certain length, and no long-chain branches.

[0006] Linear low-density polyethylene film has the characteristics of general polyethylene, as well as high breaking strength and elongation, excellent film processability and transparency, and superior tear strength and drop impact strength, so its use is increasing in industrial films such as food packaging and industrial laminated films, heavy-duty films, and stretch wrap films, where conventional low-density polyethylene or high-density polyethylene is difficult to apply.

[0007] Linear low-density polyethylene (LPE) is generally known to exhibit increased drop impact strength as density decreases. However, the use of large amounts of comonomers to manufacture LPE can lead to increased fouling during the slurry polymerization process, and the resulting film can become sticky, necessitating increased use of anti-blocking agents. Furthermore, production processes can become unstable, and the resulting polyethylene morphology can deteriorate, resulting in a decrease in bulk density.

[0008] Due to recent market trends in sustainability and D4R (Design For Recyclability), the demand for down-gauging (D / G) is increasing, and accordingly, the demand for linear low-density polyethylene with excellent molding processability and drop impact strength is also increasing.

[0009] Before COVID-19, D / G was focused on reducing the thickness of the polyethylene layer in multilayer films from a cost perspective. However, after COVID-19, with the increased interest in environmental issues, the demand for downgauging from a recycling perspective and the issue of energy consumption for carbon reduction have emerged.

[0010] In addition, in the existing D / G, product development was focused on lowering density to improve drop impact, but in the D / G from the D4R perspective, the trend has changed to the development of products with an excellent balance of stiffness and toughness, and as the demand for single-material film composition for recycling increases, the demand for strengthened sealing properties also increases.

[0011]

[0012] In order to solve the problems of the above prior art, the present invention aims to provide polyethylene having excellent low-temperature sealing properties and hot-tack properties.

[0013] In addition, the present invention seeks to provide a film comprising the polyethylene.

[0014]

[0015] According to the present invention, polyethylene satisfying the following conditions (a1) to (a3) ​​is provided:

[0016] (a1) Density measured according to ASTM D1505: 0.912 to 0.925 g / cm 3

[0017] (a2) Molecular weight distribution (Mw / Mn): 2.50 to 5.00

[0018] (a3) When analyzing the temperature-increasing elution fraction of cross-fraction chromatography+, based on the total weight of polyethylene,

[0019] (a3-1) The content of the polymer fraction eluted at an elution temperature of 80°C or higher is 30.0 to 55.0 wt%,

[0020] (a3-2) The content of the polymer fraction eluted at a dissolution temperature of 60°C or higher and less than 80°C is 10.0 to 50.0 wt%, and

[0021] (a3-3) The content of a polymer fraction eluted at a dissolution temperature of 30°C or higher and less than 60°C is 10.0 to 35.0 wt%.

[0022] In addition, according to the present invention, a film including the polyethylene is provided.

[0023]

[0024] The polyethylene according to the present invention exhibits excellent low-temperature sealing properties and hot-tack properties. Furthermore, the polyethylene exhibits excellent drop impact strength and rigidity, along with improved molding processability. Accordingly, downgauging is possible during film production using the polyethylene, making it advantageous for D4R applications. The polyethylene can be usefully used in multipurpose films, such as food, agricultural, and general industrial films, or stretch films, and is particularly useful in the sealant layer of All-PE.

[0025]

[0026] Figure 1a is a graph showing the relationship between the elution temperature (Te) (℃) and the number of SCBs (CH3 / 1,000C) derived through temperature rising elution fractionation (TREF) analysis of cross fractionation chromatography (CFC).

[0027] Figure 1b is a graph showing the relationship between the elution temperature (Te) (℃) and the cumulative content (wt%), which is the normalized cumulative integral value of the composition distribution curve, derived through TREF analysis of CFC.

[0028] Figure 2 shows Figures 1a and 1b together to derive a correlation between the elution temperature (Te) (℃) and the number of SCBs (CH3 / 1,000C). In the present invention, the correlation between the elution temperature and the number of SCBs is derived using the number of SCBs in the range of 25% to 75% based on 50% of the cumulative content curve.

[0029] Figure 3 is a graph showing the relationship between the comonomer content (comonomer wt%) derived from Figure 2 and the cumulative content (Sum wt%), which is the normalized cumulative integral value of the composition distribution curve.

[0030] Figure 4 is a graph showing the relationship between the elution temperature (Te) (℃) and the elution amount (dW / dT) derived from the TREF analysis results of CFCs for polyethylene of Examples 1-1 to 5-1.

[0031] Figure 5 is a graph showing the relationship between the elution temperature (Te) (℃) and the elution amount (dW / dT) derived from the TREF analysis results of CFC for polyethylene of Comparative Examples 1-1 to 5-1.

[0032] Figure 6 is a graph showing the relationship between the loss modulus (G") and the storage modulus (G') obtained from the results of measuring the rheological properties of polyethylene of Examples 1-1 to 5-1 and Comparative Examples 1-1 to 5-1.

[0033] Figure 7 shows the complex elastic modulus (G) obtained from the rheological property measurement results for polyethylene of Examples 1-1 to 5-1 and Comparative Examples 1-1 to 5-1. * ) and complex viscosity (η*).

[0034] Figure 8 is a graph showing the heat seal strength (N / 25.4 mm) according to the sealing temperature (℃) of Examples 1-2 to 5-2 and Comparative Examples 1-2 to 5-2.

[0035] Figure 9 is a graph showing the hot-tack strength (N / 25.4 mm) according to the sealing temperature (℃) of Examples 1-2 to 5-2 and Comparative Examples 1-2 to 5-2.

[0036]

[0037] 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.

[0038] 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.

[0039] Additionally, the term “to” used in describing a numerical range in this specification includes both the upper and lower limits. For example, “1 to 3” means 1 or more and 3 or less.

[0040] Also, throughout this specification, the term “polyethylene” or “ethylene (co)polymer” is a concept that includes both ethylene homopolymer and / or copolymer of ethylene and alpha-olefin.

[0041] 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.

[0042] Hereinafter, the polyethylene of the present invention and the film containing the same will be described in detail.

[0043]

[0044] The polyethylene according to the present invention satisfies the following conditions (a1) to (a3).

[0045] (a1) Density measured according to ASTM D1505: 0.912 to 0.925 g / cm 3

[0046] (a2) Molecular weight distribution (Mw / Mn): 2.50 to 5.00

[0047] (a3) When analyzing temperature-increasing elution fractions by cross-fraction chromatography, based on the total weight of polyethylene,

[0048] (a3-1) The content of the polymer fraction eluted at an elution temperature of 80°C or higher is 30.0 to 55.0 wt%,

[0049] (a3-2) The content of the polymer fraction eluted at a dissolution temperature of 60°C or higher and less than 80°C is 10.0 to 50.0 wt%, and

[0050] (a3-3) The content of a polymer fraction eluted at a dissolution temperature of 30°C or higher and less than 60°C is 10.0 to 35.0 wt%.

[0051] The conditions (a3-1) to (a3-3) above mean that the polyethylene according to the present invention has a multimodal crystal distribution with different molecular weight distributions. By having a multimodal crystal distribution in this way and controlling the molecular weight distribution according to crystallinity, the polyethylene can exhibit improved rigidity along with excellent low-temperature sealing properties and hot-tack properties.

[0052] More specifically, the polyethylene may have a content of a polymer (M1) fraction eluted at an elution temperature of 80°C or higher in TREF analysis of CFCs of 30.0 wt% or more, or 31.0 wt% or more, or 32.0 wt% or more, or 33.0 wt% or more, or 34.0 wt% or more, or 35.0 wt% or more, or 36.0 wt% or more, and 55.0 wt% or less, or 54.0 wt% or less, or 53.0 wt% or less, or 52.0 wt% or less, or 51.0 wt% or less, or 50.0 wt% or less, or 49.0 wt% or less, or 48.0 wt% or less, or 47.0 wt% or less, or 46.6 wt% or less, or 46.0 wt% or less, or 45.0 wt% or less, or 40.0 wt% or less, based on the total weight of the polyethylene.

[0053] The M1 fraction content affects the stiffness of polyethylene film production. Lower M1 fraction content leads to lower stiffness. On the other hand, if the M1 fraction content exceeds 55.0 wt% and the elution temperature is too high (35°C), <Te<60℃에서의 용출되는 중합체 분획의 중량평균 분자량이 지나치게 클 경우 폴리에틸렌의 저온 실링 특성이 오히려 저하될 수 있다. 본 발명에 따른 폴리에틸렌은 M1을 상기한 함량 범위로 포함함에 따라, 우수한 강성을 나타낼 수 있다.

[0054] In addition, the polyethylene has a content of a polymer (M2) fraction that elutes at an elution temperature of 60°C or higher and less than 80°C of 10.0 wt% or more, or 11.0 wt% or more, or 12.0 wt% or more, or 13.0 wt% or more, or 14.0 wt% or more, or 15.0 wt% or more, or 16.0 wt% or more, or 17.0 wt% or more, or 18.0 wt% or more, or 19.0 wt% or more, or 19.5 wt% or more, or 19.8 wt% or more, or 20.0 wt% or more, or 21.0 wt% or more, or 22.0 wt% or more, or 23.0 wt% or more, or 24.0 wt% or more, or 25.0 wt% or more, or 26.0 wt% or more, or 27.0 wt% or more, or 28.0 wt% or more than 29.0 wt%, or more than 30 wt%, and 50.0 wt% or less, or 49.0 wt% or less, or 48.0 wt% or less, or 47.0 wt% or less, or 46.0 wt% or less, or 45.0 wt% or less, or 44.0 wt% or less, or 43.0 wt% or less, or 42.0 wt% or less, or 41.0 wt% or less, or 40.0 wt% or less, or 39.0 wt% or less, or 38.0 wt% or less, or 37.0 wt% or less, or 36.0 wt% or less, or 35.0 wt% or less, or 34.0 wt% or less, or 33.5 wt% or less, or 33.2 wt% or less, or 33.0 wt% or less.

[0055] The range of the above elution temperature of 60℃ or more and less than 80℃ is a major section that determines the density and MI of polyethylene. Typically, linear low-density polyethylene (LLDPE) with a density of 0.925 g / cm3 or less has a high crystal distribution in the above elution temperature range. In this regard, the polyethylene according to the present invention can exhibit excellent low-temperature sealing properties and hot-tack properties by containing the M2 fraction in the above-mentioned content range while having a low density. On the other hand, in the case of polyethylene in which the content of the M2 fraction is less than 10.0 wt% and the content of the M3 fraction is high, that is, in which many crystals are distributed at Te 80℃ or more, the polyethylene exhibits a high density, so that the low-temperature sealing properties and hot-tack properties are greatly deteriorated.

[0056] In addition, the polyethylene has a content of a polymer (M3) fraction that elutes at an elution temperature of 30° C. or higher and less than 60° C. of 10.0 wt% or more, or 11.0 wt% or more, or 12.0 wt% or more, or 13.0 wt% or more, or 14.0 wt% or more, or 15.0 wt% or more, or 16.0 wt% or more, or 17.0 wt% or more, or 18.0 wt% or more, or 19.0 wt% or more, or 20.0 wt% or more, or 21.0 wt% or more, or 22.0 wt% or more, or 23.0 wt% or more, or 24.0 wt% or more, or 25.0 wt% or more, or 26.0 wt% or more, or 27.0 wt% or more, or 28.0 wt% or more, or 29.0 wt% or more, or 30.0 wt% and may be 35.0 wt% or less, or 34.5 wt% or less, or 34.0 wt% or less, or 33.5 wt% or less, or 33 wt% or less.

[0057] The polymer (M3) eluted in the range of the above elution temperature of 30°C or more and less than 60°C delays secondary crystallization between the die and the frost line during blown film production, and as a result, reduces the size of the crystal lamellae, thereby improving the low-temperature sealing characteristics and hot-tack characteristics. However, if the content of the M3 fraction is less than 10.0 wt%, the low-temperature sealing characteristics and hot-tack characteristics may deteriorate due to the increase in lamellae resulting from the increase in the crystallization rate. On the other hand, if the content of the M3 exceeds 35.0 wt%, the low-crystal content affecting the mechanical strength characteristics relatively increases, and thus the rigidity may deteriorate during film production.

[0058] In addition, the polyethylene according to the present invention can exhibit even better drop impact strength properties and low-temperature sealing properties by having controlled molecular weight distribution properties in addition to the crystal distribution properties described above.

[0059] Specifically, the polyethylene has an elution temperature of more than 35°C and less than 60°C in TREF analysis of CFC (35°C <Te<60℃) 용출되는 중합체(M4) 분획의 중량평균 분자량(Mw)이 60,000 내지 190,000 g / mol이다. 보다 구체적으로는 60,000 g / mol 이상, 또는 70,000 g / mol 이상 또는 80,000 g / mol 이상, 또는 90,000 g / mol 이상, 또는 92,000 g / mol 이상, 또는 92,500 g / mol 이상, 또는 92,700 g / mol 이상이고, 190,000 g / mol 이하, 또는 180,000 g / mol 이하, 또는 170,000 g / mol 이하, 또는 160,000 g / mol 이하, 또는 150,000 g / mol 이하, 또는 149,000 g / mol 이하, 또는 140,000 g / mol 이하, 또는 130,000 g / mol 이하, 또는 125,000 g / mol 이하, 또는 120,000 g / mol 이하, 또는 110,000 g / mol 이하, 또는 100,000 g / mol 이하일 수 있다.

[0060] The weight average molecular weight of the M4 fraction refers to the weight average molecular weight of the polymer fraction in the low crystallinity region, and it affects the low-temperature sealing properties and drop impact strength in relation to the formation of tie molecules. In general, the drop impact strength of linear low-density polyethylene increases when the lamellar structure with an appropriate level of crystallinity is connected by tie chains. In other words, in order to increase the drop impact strength, it is necessary to have sufficient low crystallinity so that the high molecular weight chains that can become ties can diverge into the amorphous region. According to the sealing mechanism, when two different films are bonded, wetting occurs due to heat and pressure, the molecular chains are melted / dispersed, and rearrangement of the molecular chains occurs, and then sealing occurs through the rearrangement of crystals during cooling. At this time, a large weight average molecular weight of the M4 fraction is advantageous in terms of dispersibility. However, if the weight average molecular weight is excessively high, for example, if the molecular weight of M4 exceeds 190,000 g / mol, the low-temperature sealing properties actually deteriorate. The polyethylene according to the present invention can exhibit excellent low-temperature sealing properties and drop impact strength properties as the molecular weight in the low crystallinity region satisfies the above-described range conditions.

[0061] In addition, the polyethylene, when analyzed by TREF of CFC with the above-mentioned molecular weight distribution conditions, has an elution temperature of more than 35°C and less than 60°C (35°C) <Te<60℃) 용출되는 중합체(M4) 분획의 함량이 폴리에틸렌 총 중량 기준으로, 5.0 내지 30.0 중량%의 조건을 더 만족할 수 있다. 보다 구체적으로는 상기 용리 온도 35℃ 초과이고 60 ℃ 미만에서 용출되는 중합체 분획의 함량이 폴리에틸렌 총 중량 기준으로, 5.0중량% 이상, 또는 6.0중량% 이상, 또는 7.0중량% 이상, 또는 8.0중량% 이상, 또는 8.5중량% 이상, 또는 9.0중량% 이상, 또는 10.0중량% 이상, 또는 11.0중량% 이상, 또는 12.0중량% 이상, 또는 13.0중량% 이상, 또는 14.0중량% 이상, 또는 15.0중량% 이상이고, 30.0중량% 이하, 또는 29.0중량% 이하, 또는 28.0중량% 이하, 또는 27.0중량% 이하, 또는 26.0중량% 이하, 또는 25.0중량% 이하, 또는 24.0중량% 이하, 또는 23.0중량% 이하, 또는 22.0중량% 이하, 또는 21.0중량% 이하일 수 있다.

[0062] The polyethylene according to the present invention can exhibit even better low-temperature sealing properties and drop impact strength properties by satisfying the molecular weight conditions and content conditions in the above-described low-crystal region.

[0063] Meanwhile, in the present invention, the weight average molecular weight (Mw) of the fractions eluted at each temperature in the TREF analysis of CFC can be measured through GPC analysis. Specifically, the fractions eluted at each temperature in the TREF analysis of the CFC can be measured using a GPC device (Polymer Char GPC-IR). ®) and then transferred to a GPC Column (Polymer Laboratories PLgel MIX-B 300 mm length column), analysis can be performed under the conditions of a measurement temperature of 100°C to 200°C, specifically 160°C, a solvent of 1,2,4-trichlorobenzene, and a flow rate of 0.1 mL / min to 10 mL / min, specifically 1 mL / min. At this time, a sample having a concentration of 1 mg / 10mL to 20mg / 10mL, specifically 16mg / 8mL, can be supplied in an amount of 100 μL to 300 μL, specifically 200 μL. The Mw value is derived using a calibration curve formed using a polystyrene standard specimen. At this time, the weight average molecular weight of the polystyrene standard specimen can be used as nine types, for example, 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.

[0064] In addition, the polyethylene according to the present invention has a low density in addition to the above-described crystal distribution characteristics.

[0065] Specifically, the polyethylene has a density of 0.912 to 0.925 g / cm as measured according to ASTM D1505. 3 am.

[0066] The density of polyethylene is 0.912 g / cm 3 If it is less than 0.925 g / cm, it is difficult to ensure stability in the slurry polymerization process. In addition, density and drop impact strength have a trade-off relationship, and the density of polyethylene is 0.925 g / cm 3 If it exceeds, it is difficult to down-gauge during film production due to the decrease in drop impact strength. More specifically, the polyethylene according to the present invention has a density of 0.912 g / cm 3 or 0.913 g / cm 3or 0.914 g / cm 3 or 0.915 g / cm 3 or 0.916 g / cm 3 or 0.925 g / cm 3 or less, or 0.924 g / cm 3 or less, or 0.923 g / cm 3 or less, or 0.922 g / cm 3 or less, or 0.921 g / cm 3 or less, or 0.920 g / cm 3 or less, or 0.919 g / cm 3 or less, or 0.918 g / cm 3 or less, or 0.917 g / cm 3 It could be as follows:

[0067] In addition, the polyethylene according to the present invention has a molecular weight distribution (MWD, Mw / Mn) of 2.50 to 5.00.

[0068] If the molecular weight distribution is narrow, less than 2.50, the mechanical properties such as toughness are excellent, but there is a risk that the molding processability may deteriorate. If the molecular weight distribution exceeds 5.00, the molding processability is excellent, but there is a risk that the mechanical properties may deteriorate. More specifically, the polyethylene has a molecular weight distribution (MWD) of 2.50 or more, or 2.60 or more, or 2.70 or more, or 2.80 or more, or 2.90 or more, or 3.00 or more, or 3.10 or more, or 3.20 or more, or 3.30 or more, or 3.40 or more, or 3.50 or more, or 3.60 or more, or 3.70 or more, or 3.75 or more, or 3.76 or more, and 5.00 or less, or 4.90 or less, or 4.80 or less, or 4.70 or less, or 4.60 or less, or 4.50 or less, or 4.40 or less, or 4.30 or less, or 4.26 or less, or 4.20 or less, or 4.10 or less, or 4.00 or less, or 3.90 or less, or 3.80 The polyethylene according to the present invention can exhibit well-balanced improved molding processability and mechanical properties by satisfying the above-mentioned molecular weight distribution conditions.

[0069] Meanwhile, in the present invention, the weight average molecular weight (Mw) and number average molecular weight (Mn) of polyethylene were measured using gel permeation chromatography (GPC), and then the molecular weight distribution was calculated as the ratio of the weight average molecular weight to the number average molecular weight (Mw / Mn). Here, the weight average molecular weight (Mw) and number average molecular weight (Mn) are polystyrene-converted molecular weights analyzed by GPC.

[0070] Specifically, a sample of polyethylene was analyzed using a Polymer Char GPC-IR using a Polymer Laboratories PLgel MIX-B 300 mm length column. ®The evaluation was performed using a device. The evaluation temperature was 160℃, 1,2,4-trichlorobenzene was used as a solvent, and the flow rate was measured at a rate of 1 mL / min. The polyethylene sample was prepared at a concentration of 16 mg / 8 mL and then supplied in an amount of 200 μL. The values ​​of Mw and Mn were measured using a calibration curve formed using polystyrene standards. The molecular weights of the polystyrene standards were 9 types: 2,000 / 10,000 / 30,000 / 70,000 / 200,000 / 700,000 / 2,000,000 / 4,000,000 / 10,000,000.

[0071] In addition, the polyethylene according to the present invention has a melt index (MI) measured at a temperature of 190°C and a load of 2.16 kg according to ASTM D1238 standard. 2.16) is 0.50 to 5.00 g / 10 min. More specifically, 0.50 g / 10 min or more, or 0.60 g / 10 min or more, or 0.70 g / 10 min or more, or 0.80 g / 10 min or more, or 0.90 g / 10 min or more, or 1.00 g / min or more, or 1.10 g / 10 min or more, or 1.20 g / min or more, or 1.30 g / min or more, or 1.35 g / min or more, and 5.00 g / 10 min or less, or 4.90 g / 10 min or less, or 4.80 g / 10 min or less, or 4.70 g / 10 min or less, or 4.60 g / 10 min or less, or 4.50 g / 10 min or less, or 4.40 g / 10 min or less, or 4.30 g / 10 min or less, or 4.20 g / 10 min or less, or 4.10 g / 10min or less, or 4.00 g / 10min or less, or 3.90 g / 10min or less, or 3.80 g / 10min or less, or 3.70 g / 10min or less, or 3.60 g / 10min or less, or 3.50 g / 10min or less, or 3.40 g / 10min or less, or 3.30 g / 10min or less, or 3.20 g / 10min or less, or 3.10 g / 10min or less, or 3.00 g / 10min or less, or 2.90 g / 10min or less, or 2.80 g / 10min or less, or 2.70 g / 10min or less, or 2.60 g / 10min or less, or 2.50 g / 10min or less, or 2.40 g / 10min or less, or 2.30 g / 10min or less, or 2.20 g / 10 min or less, or 2.10 g / 10 min or less, or 2.00 g / 10 min or less, or 1.90 g / 10 min or less, or 1.80 g / 10 min or less, or 1.70 g / 10 min or less, or 1.60 g / 10 min or less, or 1.50 g / 10 min or less, or 1.40 g / 10 min or less.

[0072] In addition to the aforementioned crystal distribution characteristics and molecular weight distribution characteristics, the polyethylene according to the present invention can exhibit improved molding processability and mechanical properties as well as excellent sealing properties and drop impact strength characteristics by satisfying the conditions of low density and optimal range molecular weight distribution and melting index.

[0073] In addition, the polyethylene according to the present invention satisfies one or more, two or more, or all three of the following conditions (c1) to (c3):

[0074] (c1) ER (Polydispersity at the High MW): 0.10 to 2.00 dyn / cm calculated according to the following mathematical formula 4 2 ,

[0075] (c2) PDR (Overall Polydispersity): 2.5 to 20.0 calculated according to the following mathematical formula 5.

[0076] (c3) The zero shear viscosity (η) calculated according to the following mathematical equation 6 0 ): 6,000 to 20,000 Pa·s

[0077] [Equation 4]

[0078]

[0079] In the above mathematical formula 4,

[0080] C1 is a constant, 1.781x10 -3 And,

[0081] G' is the storage modulus of polyethylene (dyne / cm 2 ) and

[0082] G"ref is the loss modulus of polyethylene, 5000 dyne / cm 2 am.

[0083] [Equation 5]

[0084]

[0085] In the above mathematical expression 5, η*1, η*2, and η*3 are the reference complex modulus G, respectively. * ref1 , G * ref2 , and G * ref3 As a complex viscosity in the present invention, G * ref1 =1.95x10 4 dyne / cm 2 And, G * ref2 =(G * ref1 G * ref3 ) 1 / 2 , and for linear polymers, log10(G * ref3 / G * ref1 ) is calculated based on 2.

[0086] [Equation 6]

[0087]

[0088] In the above mathematical expression 6, N is the number of modes, and G i is the elastic modulus (dyne / cm) corresponding to the relaxation time. 2 ), and τ i is the relaxation time (s).

[0089] Specifically, the polyethylene has an ER (Polydispersity at the High MW) of 0.10 to 2.00 dyn / cm, determined according to the above mathematical formula 4. 2 That's all.

[0090] ER, also known as rheological polydispersity, is derived from measurements of the rheological properties (or rheological properties) of polymer melts. The rheological properties of polymer melts are highly dependent on their underlying molecular structure, specifically molecular weight, molecular weight distribution, and long chain branching (LCB). ER quantifies polydispersity at high Mw, independent of molecular weight and molecular weight distribution in polyethylene.

[0091] A higher ER value indicates greater polydispersity at high Mw and the presence of molecules with long relaxation times. A lower ER value indicates less polydispersity at high Mw and the presence of molecules with short relaxation times.

[0092] More specifically, the polyethylene according to the present invention has an ER of 0.10 dyn / cm 2 or 0.20 dyn / cm 2 or 0.30 dyn / cm 2 or 0.40 dyn / cm 2 or 0.50 dyn / cm 2 or 0.60 dyn / cm 2 or 0.70 dyn / cm 2 or 0.80 dyn / cm 2 or 0.90 dyn / cm 2 or 1.00 dyn / cm 2 or 1.10 dyn / cm 2 ideal, or 1.11 dyn / cm 2 or 1.12 dyn / cm 2 ideal, or 1.13 dyn / cm 2 ideal, or 1.14 dyn / cm 2 or 1.15 dyn / cm 2 or 1.16 dyn / cm 2 ideal, or 1.17 dyn / cm 2 ideal, or 1.18 dyn / cm 2Above, 1.19 dyn / cm 2 or 1.20 dyn / cm 2 ideal, or 1.21 dyn / cm 2 ideal, or 1.22 dyn / cm 2 ideal, or 1.23 dyn / cm 2 ideal, or 1.24 dyn / cm 2 or 1.25 dyn / cm 2 ideal, or 1.26 dyn / cm 2 ideal, or 1.27 dyn / cm 2 ideal, or 1.28 dyn / cm 2 ideal, or 1.29 dyn / cm 2 or 1.30 dyn / cm 2 ideal, or 1.31 dyn / cm 2 ideal, or 1.32 dyn / cm 2 ideal, or 1.33 dyn / cm 2 ideal, or 1.34 dyn / cm 2 ideal, or 1.35 dyn / cm 2 ideal, or 1.36 dyn / cm 2 ideal, or 1.37 dyn / cm 2 ideal, or 1.38 dyn / cm 2 ideal, or 1.39 dyn / cm 2 or 1.40 dyn / cm 2 ideal, or 1.41 dyn / cm 2 ideal, or 1.42 dyn / cm 2 ideal, or 1.43 dyn / cm 2 ideal, or 1.44 dyn / cm 2 ideal, or 1.45 dyn / cm 2 Above, 2.00 dyn / cm 2 or less, or 1.99 dyn / cm 2 or less, or 1.98 dyn / cm 2 or less, or 1.97 dyn / cm 2 or less, or 1.96 dyn / cm 2or less, or 1.95 dyn / cm 2 or less, or 1.94 dyn / cm 2 or less, or 1.93 dyn / cm 2 or less, or 1.92 dyn / cm 2 or less, or 1.91 dyn / cm 2 or less, or 1.90 dyn / cm 2 or less, or 1.89 dyn / cm 2 or less, or 1.88 dyn / cm 2 or less, or 1.87 dyn / cm 2 or less, or 1.86 dyn / cm 2 or less, or 1.85 dyn / cm 2 or less, or 1.84 dyn / cm 2 or less, or 1.83 dyn / cm 2 or less, or 1.82 dyn / cm 2 or less, or 1.81 dyn / cm 2 or less, or 1.80 dyn / cm 2 or less, or 1.79 dyn / cm 2 or less, or 1.78 dyn / cm 2 or less, or 1.77 dyn / cm 2 or less, or 1.76 dyn / cm 2 or less, or 1.75 dyn / cm 2 or less, or 1.74 dyn / cm 2 or less, or 1.73 dyn / cm 2 or less, or 1.72 dyn / cm 2 or less, or 1.71 dyn / cm 2 or less, or 1.70 dyn / cm 2 or less, or 1.69 dyn / cm 2 or less, or 1.68 dyn / cm 2 or less, or 1.67 dyn / cm 2 or less, or 1.66 dyn / cm 2 or less, or 1.65 dyn / cm 2 or less, or 1.64 dyn / cm 2or less, or 1.63 dyn / cm 2 or less, or 1.62 dyn / cm 2 or less, or 1.61 dyn / cm 2 or less, or 1.60 dyn / cm 2 or less, or 1.59 dyn / cm 2 or less, or 1.58 dyn / cm 2 or less, or 1.57 dyn / cm 2 or less, or 1.56 dyn / cm 2 or less, or 1.55 dyn / cm 2 or less, or 1.54 dyn / cm 2 or less, or 1.53 dyn / cm 2 or less, or 1.52 dyn / cm 2 or less, or 1.51 dyn / cm 2 or less, or 1.50 dyn / cm 2 The polyethylene according to the present invention can exhibit excellent molding processability by satisfying the ER conditions within the above-described range.

[0093] Meanwhile, ER can be calculated by the method disclosed in “New measures of polydispersity from rheological data on polymer melts”, Journal of Applied Polymer Science, vol. 57, 1605~1626 (1995). The method and conditions for measuring ER in the present invention are as described in the following experimental examples.

[0094] In addition, the polyethylene according to the present invention has an Overall Polydispersity (PDR) of 2.5 to 20.0 determined according to the above mathematical formula 5:

[0095] In the above mathematical expression 5, η*1, η*2, and η*3 are the reference complex elastic moduli G, respectively. * ref1 , G * ref2 , and G * ref3is the complex viscosity in . In the present invention, G * ref1 =1.95x10 4 dyn / cm 2 And, G * ref2 = (G * ref1 G * ref3 ) 1 / 2 , and for linear polymers, log10(G * ref3 / G * ref1 )=2 were used as the standard to obtain η*1, η*2, and η*3.

[0096] ER does not reflect contributions from low MW. Therefore, if we are interested in overall polydispersity, i.e. both high and low MW contributions, then the complex modulus (G * ) uses the PDR function.

[0097] PDR represents the overall polydispersity of polyethylene, and in the above mathematical formula 5 represents shear sensitivity, represents the curvature of the viscosity curve. A higher PDR means greater shear sensitivity and polydispersity, resulting in better moldability. A lower PDR means less shear sensitivity and polydispersity, resulting in worse moldability.

[0098] More specifically, the polyethylene according to the present invention has a PDR of 2.5 or more, or 2.6 or more, or 2.7 or more, or 2.8 or more, or 2.9 or more, or 3.0 or more, or 3.1 or more, or 3.2 or more, or 3.3 or more, or 3.4 or more, or 3.5 or more, or 3.6 or more, or 3.7 or more, or 3.8 or more, or 3.9 or more, or 4.0 or more, or 4.1 or more, or 4.2 or more, or 4.3 or more, or 4.4 or more, or 4.5 or more, or 4.6 or more, or 4.7 or more, or 4.8 or more, or 4.9 or more, or 5.0 or more, or 5.1 or more, or 5.2 or more, or 5.3 or more, or 5.4 or more, or 5.5 or more, or 5.6 or more, and 20.0 or less, or 19.0 or less, or 18.0 or less, or 17.0 or less, or 16.0 or less, or 15.0 or less, or 14.0 or less, or 13.0 or less, or 12.0 or less, or 11.9 or less, or 11.8 or less, or 11.7 or less, or 11.6 or less, or 11.5 or less, or 11.4 or less, or 11.3 or less, or 11.2 or less, or 11.1 or less, or 11.0 or less, or 10.9 or less, or 10.8 or less, or 10.7 or less, or 10.6 or less, or 10.5 or less, or 10.4 or less, or 10.3 or less, or 10.2 or less, or 10.1 or less, or 10.0 or less. The polyethylene according to the present invention can exhibit excellent molding processability by exhibiting a PDR within the above-mentioned range.

[0099] The method and conditions for measuring PDR in the present invention are as described in the experimental examples below.

[0100] In addition, when analyzing the relaxation time spectrum, the polyethylene according to the present invention exhibits a bimodal crystal distribution in a graph with the relaxation time (τ)(s) as the x-axis and τH(τ) / η0 as the y-axis. Here, s means the time unit 'second'.

[0101] This crystal distribution implies a higher content of high molecular weight polymers exhibiting long relaxation times compared to polyethylene, which exhibits a unimodal crystal distribution. Consequently, crystal growth rates can be easily controlled, resulting in superior drop impact strength.

[0102] The relaxation time spectrum is calculated from experimental results for measuring material constants. Specifically, by applying shear strain to polyethylene and measuring the response to the strain using a rheometer, the relaxation modulus G(t) and the dynamic modulus (storage modulus G'(ω) and loss modulus G"(ω))) as a function of time (t) or frequency (ω) can be determined, respectively, based on the response of the polyethylene and the structure and shape of the rheometer used (see JM Dealy and KF Wissbrun, Melt Rheology and Its Role in Plastics Processing, Van Nostrand Reinhold, 1990, pp. 269-297).

[0103] The relaxation time spectrum can be expressed in a continuous or discontinuous form. After obtaining G'(ω) and G"(ω), it is analyzed by spectral factors. The continuous relaxation time spectrum is calculated through integration as follows, and the discrete relaxation time spectrum (or discontinuous relaxation time spectrum) is calculated by dividing it according to the specified number of divisions, i.e. the number of modes (N), as follows (Park Seung-jun et al., The Korean J. of Rheology, 1996(8) 103-118).

[0104] <Continuous relaxation time spectrum, H(t)>

[0105] (1)

[0106] (2)

[0107] <Discrete relaxation time spectrum, G i >

[0108] (3)

[0109] (4)

[0110] In the above mathematical equations (1) to (4), G'(ω) is the storage modulus, and G"(ω) is the loss modulus.

[0111] Also, H(τ) represents the relaxation time spectrum, ω is the frequency (rad / s), τ is the continuous relaxation time (s), and τ i represents the discrete relaxation time (s).

[0112] Also, N is the number of modes in the mode distribution of the relaxation time spectrum, and G i is the elastic modulus (dyne / cm) corresponding to the relaxation time. 2 )am.

[0113] The mode distribution of a relaxation spectrum can also be calculated using software such as IRIS Rheology Software (IRIS Development). Once the mode distribution in a relaxation spectrum is calculated, the first and second moments of the distribution (which are analogous to the first and second moments of the molecular weight distribution, Mn and Mw) can be calculated as follows.

[0114] (i)

[0115] (ii)

[0116] In the above mathematical equations (i) and (ii), N is the number of modes in the mode distribution of the relaxation time spectrum, and G i is the elastic modulus (dyne / cm) corresponding to the relaxation time. 2 ), and τ i is the relaxation time (s).

[0117] Zero shear viscosity (η0) can also be calculated using the above relaxation time spectrum analysis results.

[0118] Specifically, the polyethylene according to the present invention has a zero shear viscosity (η) calculated according to the above mathematical expression 6 from the relaxation time spectrum analysis results. 0) is 6,000 to 20,000 Pa·s or less. More specifically, the polyethylene has a zero shear viscosity of 6,000 Pa·s or more, or 7,000 Pa·s or more, or 7,100 Pa·s or more, or 7,200 Pa·s or more, or 7,300 Pa·s or more, or 7,400 Pa·s or more, or 7,500 Pa·s or more, or 7,600 Pa·s or more, or 7,700 Pa·s or more, or 7,800 Pa·s or more, or 7,900 Pa·s or more, or 8,000 Pa·s or more, or 8,100 Pa·s or more, or 8,200 Pa·s or more, or 8,300 Pa·s or more, or 8,400 Pa·s or more, or 8,500 Pa·s or more, or 8,600 Pa·s or more, or 8,700 Pa·s or more, or 8,800 Pa·s or more, or 8,900 Pa·s or more, or 9,000 Pa·s or more, or 9,100 Pa·s or more, or 9,200 Pa·s or more, or 9,300 Pa·s or more, or 9,400 Pa·s or more, or 9,500 Pa·s or more, but not more than 20,000 Pa·s, or 19,500 Pa·s or less, or 19,000 Pa·s or less, or 18,500 Pa·s or less, or 18,000 Pa·s or less, or 17,500 Pa·s or less, or 17,000 Pa·s or less, or 16,500 Pa·s or less, or 16,000 Pa·s or less, or 15,500 Pa·s or less, or 15,000 Pa·s or less, or 14,500 Pa·s or less, or 14,000 Pa·s or less, or 13,500 Pa·s or less, or 13,000 Pa·s or less, or 12,500 Pa·s or less, or 12,000 Pa·s or less, or 11,500 Pa·s or less, or 11,000 Pa·s or less, or 10,500 Pa·s or less, or 10,000 Pa·s or less.

[0119] The polyethylene according to the present invention has rheological properties controlled within an optimal range as described above, and thus can exhibit excellent molding processability and drop impact strength properties.

[0120] In addition, the polyethylene according to one embodiment of the present invention may be a copolymer of ethylene and alpha-olefin, specifically including an alpha-olefin repeating unit derived from an alpha-olefin monomer together with an ethylene repeating unit.

[0121] The above alpha-olefin monomer may specifically be an alpha-olefin monomer having 3 to 20 carbon atoms. Specific examples thereof include propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene, 1-undecene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-eicosene, etc., and more preferably, it may be 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, or 1-octene. Preferably, the polyethylene according to one embodiment of the present invention may be a type of copolymer of ethylene and 1-hexene, rather than a mixture with another polyethylene.

[0122] Polyethylene having the above properties can be produced by a production method including, for example, a step of polymerizing an ethylene monomer and an alpha-olefin monomer in the presence of a hybrid supported metallocene catalyst comprising a first transition metal compound represented by the following chemical formula 1; and a second transition metal compound represented by the following chemical formula 2. The above production method is merely an example for implementing the polyethylene according to the present invention, and the polyethylene of the present invention is not limited to the above production method.

[0123] [Chemical Formula 1]

[0124]

[0125] In the above chemical formula 1,

[0126] M1 is a group 4 transition metal,

[0127] X 11and X 12 are each independently, C 1-20 Alkyl or halogen,

[0128] A1 is carbon, silicon, or germanium,

[0129] Q 11 and Q 12 are each independently hydrogen, halogen, C 1-20 Alkyl, or C 2-20 It is an alkoxyalkyl,

[0130] R 11 Inland R 15 are each independently hydrogen or C 1-20 It is alkyl,

[0131] [Chemical Formula 2]

[0132]

[0133] In the above chemical formula 2,

[0134] M2 is a group 4 transition metal,

[0135] X 21 and X 22 are each independently, C 1-20 Alkyl or halogen,

[0136] R 21 Inland R 25 are each independently, C 1-20 It is alkyl,

[0137] R 26 is hydrogen or C 1-20 It is alkyl,

[0138] R 27 Silver hydrogen, C 1-20 Alkyl, C 2-20 Alkoxy, or C 2-20 It is an alkoxyalkyl.

[0139]

[0140] In the present invention, the substituents of the chemical formula are described more specifically as follows.

[0141] The halogen can be fluorine (F), chlorine (Cl), bromine (Br), or iodine (I).

[0142] C 1-20 The alkyl of may be straight-chain, branched-chain or cyclic alkyl. Specifically, the C 1-20 The alkyl may be a straight chain alkyl having 1 to 20 carbon atoms; a straight chain alkyl having 1 to 10 carbon atoms; a straight chain alkyl having 1 to 5 carbon atoms; a branched chain or cyclic alkyl having 3 to 20 carbon atoms; a branched chain or cyclic alkyl having 3 to 15 carbon atoms; or a branched chain or cyclic alkyl having 3 to 10 carbon atoms. More specifically, the alkyl having 1 to 20 carbon atoms 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, or a cyclohexyl group.

[0143] C 2-20 The alkenyl of may be a straight-chain, branched-chain or cyclic alkenyl. Specifically, the C 2-20 The alkenyl may be a straight chain alkenyl having 2 to 20 carbon atoms, a straight chain alkenyl having 2 to 10 carbon atoms, a straight chain alkenyl having 2 to 5 carbon atoms, a branched chain alkenyl having 3 to 20 carbon atoms, a branched chain alkenyl having 3 to 15 carbon atoms, a branched chain alkenyl having 3 to 10 carbon atoms, a cyclic alkenyl having 5 to 20 carbon atoms or a cyclic alkenyl having 5 to 10 carbon atoms. More specifically, C 2-20 The alkenyl may be ethenyl, propenyl, butenyl, pentenyl or cyclohexenyl.

[0144] C 1-20 The alkoxy of may be a straight-chain, branched-chain or cyclic alkoxy group. Specifically, the C 1-20The alkoxy may be a straight chain alkoxy group having 1 to 20 carbon atoms; a straight chain alkoxy group having 1 to 10 carbon atoms; a straight chain alkoxy group having 1 to 5 carbon atoms; a branched chain or cyclic alkoxy group having 3 to 20 carbon atoms; a branched chain or cyclic alkoxy group having 3 to 15 carbon atoms; or a branched chain or cyclic alkoxy group having 3 to 10 carbon atoms. More specifically, the alkoxy group having 1 to 20 carbon atoms may be a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, an iso-butoxy group, a tert-butoxy group, an n-pentoxy group, an iso-pentoxy group, a neo-pentoxy group, or a cyclohexene group.

[0145] C 2-20 Alkoxyalkyl of -R y -OR z Alkyl (-R) with a structure containing y ) is one or more hydrogens of alkoxy (-OR z ) may be a substituent substituted with. Specifically, the alkoxyalkyl having C2 to C20 carbon atoms may be a methoxymethyl group, a methoxyethyl group, an ethoxymethyl group, an iso-propoxymethyl group, an iso-propoxyethyl group, an iso-propoxyhectyl group, a tert-butoxymethyl group, a tert-butoxyethyl group, or a tert-butoxyhexyl group.

[0146] Also, group 4 transition metals can include titanium, zirconium, and hafnium.

[0147]

[0148] The hybrid supported metallocene catalyst used in the production of polyethylene according to the present invention is a hybrid catalyst comprising a first transition metal compound with high molecular weight and high polymerizability, and a second transition metal compound with low molecular weight and low polymerizability.

[0149] Specifically, the first transition metal compound represented by the above chemical formula 1 contributes to producing a high molecular weight copolymer having a high SCB content, and the second transition metal compound represented by the above chemical formula 2 contributes to producing a low molecular weight copolymer having a low SCB content. Accordingly, the hybrid supported metallocene catalyst can exhibit high copolymerizability in the high molecular weight region of polyethylene due to the first transition metal compound, while exhibiting low copolymerizability in the low molecular weight region of polyethylene due to the action of the second transition metal compound. As a result, the polyethylene produced using the hybrid supported metallocene catalyst can easily produce polyethylene that satisfies the above-described physical property requirements through tie-molecule formation due to strong low crystallinity expression in the high molecular weight region.

[0150] Specifically, in the hybrid supported metallocene catalyst, the first transition metal compound represented by the chemical formula 1 contributes to the production of a high molecular weight copolymer and exhibits a relatively high comonomer incorporation rate compared to the second transition metal compound.

[0151] Specifically, in the above chemical formula 1, M1 may be zirconium (Zr) or titanium (Ti).

[0152] Also, X 11 and X 12 are each independently halogen, and more specifically, may be chloro.

[0153] Also, in the above chemical formula 1, A1 is silicon, and Q 11 and Q 12 are each independently hydrogen, halogen, C 1-20 Alkyl, or C 2-20 Alkoxyalkyl, Q 11 and Q 12 Either one of C 2-20 It may be a tether group of an alkoxyalkyl. More specifically, Q 11 and Q 12 One of them is C2-20 Alkoxyalkyl, and the other one is C 1-20 It could be an alkyl.

[0154] As a bridging group connecting two ligands, Q 11 and Q 12 Either one of C 2-20 When the tether group of the alkoxyalkyl is included, the atomic size becomes larger and the available angle increases compared to the carbon bridge in the conventional metallocene compound, so that the monomer can easily approach during the polymerization reaction, thereby exhibiting excellent catalytic activity. In addition, the leaching of the catalyst precursor is prevented during the polymerization reaction, and as a result, fouling due to the reaction of the leached catalyst precursor and the cocatalyst can be prevented. Such an effect is described in the above Q 11 and Q 12 Either of them is -(CH2)nR b (Above R b is C 1-6 Alkoxy group, more specifically C 1-6 Straight chain alkoxy group or C 3-6 C, such as a branched alkoxy group, more specifically a tert-butoxy group 3-6 Branched alkoxy, n is an integer from 2 to 10, or from 3 to 9, and the remainder is C 1-4 It can be further increased in the case of alkyl. More specifically, Q 11 and Q 12 One of them may be tert-butoxyhexyl and the other may be methyl.

[0155] Also, in the above chemical formula 1, R 11 Inland R 14 are each independently, C 1-10 Alkyl, more specifically C 1-4 Alkyl, more specifically methyl. In this way, the cyclopentadienyl ligand in formula 1 is R 11 Inland R 14By being substituted, it can exhibit better catalytic activity due to the inductive effect that can supply sufficient electrons.

[0156] Also, in the above chemical formula 1, R 15 is C 1-6 It can be alkyl, more specifically C 1-4 Straight chain alkyl or C 3-6 It may be a branched alkyl, more specifically tert-butyl.

[0157] Specific examples of the first transition metal compound represented by the above chemical formula 1 include compounds having the following structures, but the present invention is not limited thereto.

[0158]

[0159]

[0160] The first transition metal compound represented by the above chemical formula 1 can be synthesized by applying known reactions, and a more detailed synthesis method can be found in the examples.

[0161] Meanwhile, in the hybrid supported metallocene catalyst, the second transition metal compound represented by the chemical formula 2 has a non-crosslinked structure of a hydrogenated indene ligand, specifically, a 4,5,6,7-tetrahydro-1-indene ligand and a cyclopentadiene ligand. Accordingly, the electronic / steric environment around the transition metal can be easily controlled, and as a result, the chemical structure, molecular weight distribution, and mechanical properties of the synthesized polyethylene can be easily controlled.

[0162] Specifically, in the above chemical formula 2, M2 may be zirconium (Zr). When the second transition metal compound includes Zr as a central metal, it has more orbitals capable of accepting electrons compared to when it includes other Group 14 elements such as Hf, and thus can easily bind to the monomer with higher affinity, resulting in a superior catalytic activity improvement effect.

[0163] Also, X 21 and X 22 can each independently be a halogen, and more specifically, a chloro.

[0164] Also, in the above chemical formula 2, R 21 Inland R 25 are each independently, C 1-10 Alkyl, more specifically C 1-4 Alkyl, more specifically methyl. Thus, the cyclopentadienyl ligand in formula 2 is R 21 Inland R 25 By being substituted, it can exhibit better catalytic activity due to the inductive effect that can supply sufficient electrons. In addition, by being used in combination with the first transition metal compound represented by the above chemical formula 1, the distribution of the comonomer in the polyethylene produced is appropriately controlled, so that polyethylene satisfying the above-described physical property requirements can be easily produced.

[0165] In addition, the second transition metal compound includes a hydrogenated indene ligand, i.e., a 4,5,6,7-tetrahydro-1-indene ligand, thereby exhibiting superior hydrogen reactivity compared to a case in which an indene group is included in the prior art. Accordingly, the amount of hydrogen input and the amount of wax generated during the polymerization reaction can be reduced, and as a result, process stability can be improved. In addition, by being used in combination with the first transition metal compound represented by the above chemical formula 1, the distribution of comonomers in the final polyethylene produced is concentrated toward a high molecular weight, and as a result, the impact strength properties of the polyethylene can be significantly improved.

[0166] In addition, the 1st and 3rd positions of the above 4,5,6,7-tetrahydro-1-indene ligand are unsubstituted, or R 26 and R 27 Each of which can be replaced by R 26 is specifically hydrogen or C 1-20 Alkyl, R 27 Silver hydrogen, C 1-20 Alkyl, C 2-20 Alkoxy, or C 2-20 It may be an alkoxyalkyl. More specifically, the R 26 is hydrogen or C 1-6 Alkyl, R 27 Silver hydrogen, C 1-6 Alkyl, or -(CH2) n -R b (Above R b is C 1-6 Alkoxy group, more specifically C 1-6 Straight chain alkoxy group or C 3-6 It may be an alkoxyalkyl group having a branched alkoxy group, and n is an integer from 2 to 10. In addition, the above -(CH2) n -R b In R b is C 3-6 C, such as a branched alkoxy group, more specifically a tert-butoxy group 3-6 Branched alkoxy, and n may be an integer from 3 to 9. More specifically, the R 26is hydrogen, or methyl, and R 27 may be hydrogen, methyl, ethyl, or tert-butoxyhexyl.

[0167] Specific examples of the second transition metal compound represented by the above chemical formula 2 include compounds having the following structures, but the present invention is not limited thereto.

[0168] .

[0169] The second transition metal compound represented by the above chemical formula 2 can be synthesized by applying known reactions, and a more detailed synthesis method can be found in the examples.

[0170] In addition, the hybrid supported metallocene catalyst can increase catalytic activity and more easily implement the properties of the polymer produced by controlling the molar ratio of the first and second transition metal compounds.

[0171] For example, the hybrid supported metallocene catalyst may include the first and second transition metal compounds in a molar ratio of 1:1 to 10:1. When the above-described mixing ratio conditions are satisfied, the catalytic activity is excellently maintained, while the high and low copolymerizabilities of the polyethylene produced from the hybrid supported catalyst are optimized, thereby further improving the sealing properties, drop impact strength properties, rigidity, and molding processability. More specifically, the molar ratio of the first and second transition metal compounds may be 2:1 to 8:1, or 2:1 to 5:1.

[0172] Additionally, the hybrid supported metallocene catalyst may include a cocatalyst.

[0173] Hybrid supported metallocene catalysts exhibit improved process stability along with high catalytic activity when they include a cocatalyst.

[0174] Specifically, the cocatalyst may include at least one compound represented by the following chemical formula 3.

[0175] [Chemical Formula 3]

[0176] -[Al(R 41 )-O]a-

[0177] In the above chemical formula 3,

[0178] R 41 is a halogen; or C substituted or unsubstituted with a halogen 1-20 It is hydrocarbyl;

[0179] a is an integer greater than or equal to 2.

[0180] Meanwhile, in the present specification, a hydrocarbyl group is a monovalent functional group in the form of removing a hydrogen atom from a hydrocarbon, and may include an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an aralkyl group, an aralkenyl group, an aralkynyl group, an alkylaryl group, an alkenylaryl group, and an alkynylaryl group. In addition, the hydrocarbyl group having 1 to 20 carbon atoms may be a hydrocarbyl group having 1 to 15 carbon atoms or 1 to 10 carbon atoms. Specifically, the hydrocarbyl group having 1 to 20 carbon atoms is a straight-chain, branched-chain, or cyclic alkyl group such as 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 n-hexyl group, an n-heptyl group, or a cyclohexyl group; Or it may be an aryl group such as a phenyl group, a naphthyl group, or anthracenyl group.

[0181] Examples of compounds represented by the above chemical formula 3 include alkylaluminoxane compounds such as methylaluminoxane, ethylaluminoxane, isobutylaluminoxane, or butylaluminoxane, and any one of these or a mixture of two or more thereof may be used. Among the above compounds, the cocatalyst may be more specifically methylaluminoxane.

[0182] The above alkylaluminoxane cocatalyst can further enhance catalytic activity by including a metal element that stabilizes the first and second transition metal compounds and acts as a Lewis acid to form a bond through a Lewis acid-base interaction with a functional group introduced to a bridge group of the first transition metal compound.

[0183] In addition, the amount of the cocatalyst used can be appropriately adjusted depending on the properties or effects of the desired catalyst and polyethylene. For example, when silica is used as the carrier described below, the cocatalyst can be supported in an amount of 100 g or more, 1000 g or more, or 2000 g or more, and 6000 g or less, or 5500 g or less, or 5400 g or less, based on the weight of the carrier, for example, 1,000 g of silica.

[0184] In addition, the hybrid supported metallocene catalyst may include a carrier. When the hybrid supported metallocene catalyst includes a carrier, the first and second transition metal compounds are used in the form of a supported catalyst supported on the carrier.

[0185] As the carrier, a carrier having a highly reactive hydroxyl group, silanol group, or siloxane group on the surface can be used. For this purpose, a carrier whose surface has been modified by calcination or whose surface has had moisture removed by drying can be used. For example, silica such as silica manufactured by calcining silica gel, or silica dried at high temperature, silica-alumina, and silica-magnesia can be used, and these can typically contain oxides, carbonates, sulfates, and nitrate components such as Na2O, K2CO3, BaSO4, and Mg(NO3)2.

[0186] When used in a supported catalyst state, the particle shape and bulk density of the polymer produced are excellent, and it can be suitably used in conventional slurry polymerization, bulk polymerization, and gas phase polymerization processes. In addition, among various supports, the silica support is supported by chemical bonding of the functional group of the transition metal compound, so that almost no catalyst is liberated from the surface of the support during the ethylene polymerization process, and as a result, fouling caused by adhesion of the reactor wall or polymer particles to each other can be minimized when producing polyethylene by slurry or gas phase polymerization.

[0187] The above-mentioned carrier may have an average particle diameter (D50) of 20 to 40 μm. When the above-mentioned particle size is present, the transition metal compound can be supported with superior efficiency, and as a result, the catalytic activity can be enhanced. More specifically, the carrier may have an average particle diameter of 20 μm or more, or 25 μm or more, and 40 μm or less, or 30 μm or less.

[0188] Meanwhile, in the present invention, the average particle diameter (D50) of the carrier refers to the particle diameter at the 50% point of the cumulative distribution of the number of particles according to particle size (particle diameter). The D50 can be measured using a laser diffraction method. Specifically, the target carrier is dispersed in a dispersion medium such as deionized water, and then introduced into a commercially available laser diffraction particle size measuring device (e.g., Microtrac S3500), and when the particles pass through the laser beam, the difference in the diffraction pattern according to the particle size is measured to calculate the particle size distribution. The particle size at the point where it becomes 50% of the cumulative distribution of the number of particles according to the particle diameter in the measuring device is calculated, and this is taken as the average particle size.

[0189] In addition, when supported on the carrier, the first and second transition metal compounds may be supported in an amount of, for example, 1.0 mmol or more, or 1.5 mmol or more, or 2.0 mmol or more, and 100 mmol or less, or 50 mmol or less, or 30 mmol or less, or 10 mmol or less, or 5.0 mmol or less, based on 1,000 g of the silica carrier. When supported in the above content range, it may exhibit appropriate supported catalytic activity, which may be advantageous in terms of maintaining the activity of the catalyst and economic efficiency.

[0190] The hybrid supported metallocene catalyst having the above-described configuration can be produced by a production method including a step of supporting a promoter compound on a support, and a step of supporting the first and second transition metal compounds on the support. In this case, the supporting order of the promoter and the first and second transition metal compounds can be changed as needed, and the supporting order of the first and second transition metal compounds can also be changed as needed. The first and second transition metal compounds can be supported simultaneously. Considering the effect of the supported catalyst having a structure determined according to the supporting order, among these, supporting the promoter on the support and then sequentially supporting the first and second transition metal compounds can enable the produced supported catalyst to realize high catalytic activity and better process stability in the process of producing polyethylene.

[0191] Meanwhile, in the polymerization reaction, specific examples of alpha-olefin monomers include, as described above, propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene, 1-undecene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-eicosene, etc., and two or more of these may be used. More specifically, the alpha-olefin monomer may be 1-hexene.

[0192] The amount of the alpha-olefin monomer added may be determined depending on the properties of the polyethylene to be manufactured. For example, considering the properties of the polyethylene to be implemented in the present invention and the effect of improving the high drop impact strength and molding processability, the alpha-olefin monomer may be added in an amount of 4 to 30 wt%, more specifically, 4 wt% or more, or 8 wt% or more, or 10 wt% or more, or 12 wt% or more, and 30 wt% or less, or 25 wt% or less, or 20 wt% or less, or 18 wt% or less, based on the total weight of monomers including ethylene and the alpha-olefin monomer.

[0193] In addition, the above polymerization reaction is performed under the condition of hydrogen input.

[0194] Specifically, hydrogen may be introduced in an amount of 10 to 50 ppm, more specifically 10 ppm or more, or 15 ppm or more, or 20 ppm or more, or 25 ppm or more, and 50 ppm or less, or 45 ppm or less, or 40 ppm or less, or 38 ppm or less, based on the total weight of monomers including ethylene monomers and alpha-olefin monomers. When introduced in the above range, it is easier to implement the physical properties of the polyethylene described above. When the polymerization reaction is performed under conditions without introducing hydrogen, the melt index (MI) of the polyethylene produced may be significantly lowered.

[0195] Additionally, the above polymerization reaction can be carried out as a slurry polymerization reaction.

[0196] In the case of solution polymerization, since the catalyst is activated by a high temperature and high pressure reaction, catalyst decomposition and chain transfer are promoted, and the resulting resin composition has a narrow molecular weight distribution (MWD) and a low high molecular weight tail content. Accordingly, the resin composition manufactured by solution polymerization exhibits deteriorated moldability when manufacturing a film. However, in the case of the slurry polymerization process of the present invention, since polymerization is performed at a relatively low temperature, it is possible to secure a molecular structure containing a wide MWD and a large amount of high molecular weight tail, which is required for a polyethylene resin composition for manufacturing a transparent film. As a result, excellent moldability can be exhibited.

[0197] In the above slurry polymerization reaction, it can be performed using a single continuous slurry polymerization reactor or a loop slurry reactor.

[0198] In addition, during the above slurry polymerization reaction, the hybrid supported catalyst can be dissolved or diluted and injected in an aliphatic hydrocarbon solvent having 4 to 12 carbon atoms, such as isobutane, pentane, hexane, heptane, nonane, decane, and isomers thereof, an aromatic hydrocarbon solvent such as toluene and benzene, a hydrocarbon solvent substituted with a chlorine atom such as dichloromethane and chlorobenzene, etc. It is preferable to use the solvent used here after removing a small amount of water or air, etc. that act as catalyst poisons, by treating it with a small amount of alkyl aluminum, and it is also possible to carry out the reaction using an additional cocatalyst.

[0199] In addition, the polymerization reaction may be carried out at a temperature of 40°C or higher, or 60°C or higher, or 80°C or higher, and 110°C or lower, or 100°C or lower, or 90°C or lower. In addition, when the pressure conditions during the polymerization reaction are further controlled, the polymerization reaction may be carried out under a pressure of 5 bar or higher, or 10 bar or higher, or 20 bar or higher, or 30 bar or higher, and 50 bar or lower, or 45 bar or lower, or 40 bar or lower. When polymerization is carried out under such temperature and pressure, the desired physical properties of polyethylene can be more easily realized.

[0200] The polyethylene produced by the above-described production method has the crystal distribution characteristics, molecular weight distribution characteristics, rheological characteristics, and processing characteristics described above. Accordingly, the polyethylene can exhibit excellent low-temperature sealing characteristics and hot-tack characteristics, and can also exhibit well-balanced improved molding processability along with excellent drop impact strength characteristics and rigidity. As a result, downgauging is possible when producing a film using the polyethylene, and the polyethylene is advantageous for D4R applications. In addition, the polyethylene can be usefully used in multi-purpose films such as food, agricultural, and general industrial films, or stretch films, and can be particularly used in the sealant layer of All-PE.

[0201] Accordingly, the present invention provides a resin composition comprising the polyethylene, specifically a composition for forming a film.

[0202] In addition, the present invention provides a film manufactured using the polyethylene or the resin composition.

[0203] The above film can be manufactured according to a conventional film manufacturing method, except that the above-mentioned polyethylene is used. For example, the film can be manufactured according to an inflation method in which a film-forming composition is manufactured by mixing only the above-mentioned polyethylene or optionally by mixing additives such as antioxidants and processing aids, and then extruding the film into a film using an extruder.

[0204] More specifically, the resin composition containing the polyethylene may be applied for a sealant layer, and co-extruded with a composition for forming another film layer, or extruded with a blown film extruder or a cast film extruder, or a film may be separately manufactured with the resin composition containing the polyethylene using extrusion coating on a substrate such as paper, and then the manufactured film may be laminated with another film. However, the present invention is not limited thereto, and any known manufacturing method may be applied to manufacture various films.

[0205] The above film exhibits excellent low-temperature sealing properties and hot-tack properties by including the above polyethylene.

[0206] Specifically, when the film is a single-layer film having a film thickness of 45 to 55 μm, or 48 to 52 μm, more specifically 50 μm, the sealing initiation temperature (SIT) measured according to ASTM F 1921 is 90.0°C or less. More specifically, the film may have a sealing initiation temperature of 90.0°C or less, or 89.0°C or less, or 88.0°C or less, or 87.0°C or less, or 86.0°C or less, or 85.0°C or less, or 84.0°C or less, or 83.0°C or less, or 82.0°C or less, or 81°C or less, when measured under the conditions of a sealing time of 0.5 seconds, a sealing pressure of 0.3 MPa, a delay time of 30.0 seconds, and a tensile speed of 200 mm / second using a J&B Hot tack tester (Hot tacker 5000) according to ASTM F 1921, at which the heat seal strength reaches 2 N / 25.4 mm. The lower the sealing initiation temperature, the better the low-temperature sealing property and sealing strength, so there is no particular limitation on the lower limit, but for example, it may be 60.0°C or higher, or 61.0°C or higher, or 62.0°C or higher, or 63.0°C or higher, or 64.0°C or higher, or 65.0°C or higher, or 66.0°C or higher, or 67.0°C or higher, or 68.0°C or higher, or 69.0°C or higher, or 70.0°C or higher.

[0207] In addition, when the film is a single-layer film having a film thickness of 45 to 55 μm, or 48 to 52 μm, more specifically 50 μm, the Hot-tack Strength measured according to ASTM F 1921 is 3.00 N / 25.4 mm or more. More specifically, when measured under the conditions of a sealing time of 0.5 seconds, a sealing pressure of 0.3 MPa, a delay time of 0.1 seconds, and a tensile speed of 200 mm / second according to ASTM F 1921, the Hot-tack Strength, which is the highest strength measured, is 3.00 N / 25.4 mm or more, or 3.10 N / 25.4 mm or more, or 3.20 N / 25.4 mm or more, or 3.30 N / 25.4 mm or more, or 3.40 N / 25.4 mm or more, or 3.50 N / 25.4 mm or more, or 3.60 N / 25.4 mm or more, or 3.70 N / 25.4 mm or more, or 3.75 N / 25.4 mm or more, or 3.80 N / 25.4 mm or more, or 3.90 N / 25.4 mm or more, or 4.00 It can be N / 25.4mm or more.

[0208] Hot-tack Strength refers to the sealing strength between two films before they are sufficiently cooled when sealed using the hot-bar jaw method. The higher the value, the better the molding processability. Accordingly, it is advantageous for VFFS packaging that enables high-speed production of hot-fill products such as ramen soup or liquid sauce. In addition, the higher the Hot-tack Strength, the advantageous for packaging heavy products. Accordingly, the upper limit of Hot-tack Strength is not particularly limited, but may be 10.00 N / 25.4mm or less, or 9.00 N / 25.4mm or less, or 8.00 N / 25.4mm or less, or 7.00 N / 25.4mm or less, or 6.00 N / 25.4mm or less, or 5.00 N / 25.4mm or less.

[0209] In addition, the polyethylene film can exhibit improved drop impact strength properties in addition to the sealing properties.

[0210] Specifically, the film has a drop impact strength of 500 gf or more, or 600 gf or more, or 700 gf or more, or 800 gf or more, or 900 gf or more, or 910 gf or more, or 920 gf or more, or 930 gf or more, or 940 gf or more, or 950 gf or more, or 960 gf or more, or 970 gf or more, measured according to ASTM D 1709 [Method A] when the film is a single-layer film having a film thickness of 45 to 55 μm, or 48 to 52 μm, more specifically 50 μm. The drop impact strength is not particularly limited in its upper limit as it is better the higher it is, but for example, it may be 3000 gf or less, or 2,900 gf or less, or 2,800 gf or less, or 2,700 gf or less, or 2,600 gf or less, or 2,500 gf or less, or 2,400 gf or less, or 2,300 gf or less, or 2,200 gf or less, or 2,100 gf or less, or 2,000 gf or less, or 1,900 gf or less, or 1,800 gf or less, or 1,700 gf or less, or 1,600 gf or less, or 1,500 gf or less.

[0211] For reference, the above sealing initiation temperature, Hot-tack Strength, and dropping impact strength were measured for a film formed into a single-layer film having a thickness of 45 to 55 μm, or 48 to 52 μm, more specifically 50 μm, using a blown film extruder (die diameter 120 mm, die gap 2.0 mm, BUR 2.5, Dual air-ring system) from a composition containing 95 wt% or more, or 96 wt% or more, or 97 wt% or more, or 98 wt% or more, or 99 wt% or more, of the polyethylene of the present invention based on the total composition.

[0212] Hereinafter, preferred examples are presented to aid understanding of the present invention. However, the following examples are provided solely to facilitate understanding of the present invention and are not intended to limit the scope of the present invention.

[0213] Meanwhile, in this specification, room temperature means 23±5℃.

[0214] <Preparation of Transition Metal Compounds>

[0215] Synthesis Example 1

[0216]

[0217]

[0218] Preparation of ligands

[0219] Tetramethylcyclopentadiene (TMCP, 1 equiv) was dissolved in THF (0.3 M), and n-BuLi (1.05 eq) was slowly added dropwise at -25°C, followed by stirring at room temperature for 3 hours. t-BuOHexSiMeCl2 (1.00 eq) was added to the resulting reaction mixture at -10°C, followed by stirring at room temperature overnight. The solvent was completely vacuum-dried, and tBuNH2 (10 eq) was added and stirred at room temperature overnight. Afterwards, the mixture was worked up with water and dried to obtain the ligand.

[0220]

[0221] Preparation of transition metal compounds

[0222] The above-mentioned ligand was dissolved in toluene (0.3 M), n-BuLi (2.05 eq) was added at -25°C, and stirred at room temperature for 3 hours. In a glove box, TiCl4(THF)2 (titanium tetrachloride tetrahydrofuran adduct, 1 eq) was prepared in another flask, added to the ligand-Li flask using a cannula at -25°C, and washed and added using toluene (1.0 M).

[0223] Upon completion of the reaction, the solvent was vacuum-dried, DCM was re-introduced, LiCl was removed through a filter, and the filtrate was vacuum-dried to obtain a liquid transition metal compound (Cat 1).

[0224] 1 H NMR (500 MHz, CDCl3) δ 3.34 (t, 2H), 2.24 (d, J = 1.7 Hz, 6H), 2.13 (d, J = 3.2 Hz, 6H), 1.57 - 1.45 (m, 6H), 1.42 (s, 9H), 1.32 - 1.22 (m, 4H), 1.18 (s, 9H), 0.67 (s, 3H).

[0225]

[0226] Synthesis Example 2-1

[0227] (Cat 2-1)

[0228] Indene (1 eq) was dissolved in THF (0.3 M), and n-BuLi (1.05 eq) was slowly added dropwise at -25°C, and the mixture was stirred at room temperature for 3 hours. Then, CH3-I (1.05 eq) was added at -10°C, and the mixture was stirred overnight at room temperature, worked up with water, and dried to obtain 3-MethylIndene. 3-MethylIndene (1 eq) thus synthesized was dissolved in THF (0.3 M), and n-BuLi (1.05 eq) was slowly added dropwise at -25°C, and the mixture was stirred at room temperature for 3 hours. Then, CH3-I (1.05 eq) was added at -10°C, and the mixture was stirred overnight at room temperature, worked up with water, and dried to obtain 1,3-dimethyl-Indene.

[0229]

[0230] Preparation of transition metal compounds

[0231] The above-mentioned ligand was dissolved in Ether (0.3 M), n-BuLi (1.05 eq) was added at -25°C, and stirred at room temperature for 3 hours. In a glove box, PMCpZrCl3 (Pentamethylcyclopentadienylzirconium trichloride) (1 eq) was prepared in another flask, added to the ligand-Li flask using a cannula at -25°C, and washed and added using Ether (1.0 M).

[0232] Upon completion of the reaction, the solvent was vacuum-dried, DCM was reintroduced, LiCl was removed through a filter, the filtrate was vacuum-dried, and slurry was formed using hexane. The resulting solid was then filtered and vacuum-dried to obtain a solid metallocene compound intermediate.

[0233]

[0234] In a glove box, the above metallocene compound intermediate was placed in a mini parr, and 5 mol% of Pd / C (10 wt%) was added. A magnetic bar was inserted here and moved outside the glove box using a closing system. DCM (0.5 M) was added to this parr, and H2 gas (10 barg) was added. After repeating the vent-charge cycle three times, the mixture was placed in a 40°C oil bath and stirred. When the pressure of the parr decreased below 5 barg, the previous charging process was repeated, and the reaction was continued until there was no more consumption of H2 gas. When the reaction was complete, the remaining H2 gas was vented and replaced with Ar gas. After cooling to room temperature, the mixture was filtered using a cannula, and the filtrate was vacuum-dried. The dried filtrate was slurried using hexane, and this was filtered to obtain a solid transition metal compound (Cat 2-1).

[0235] 1 H NMR (500 MHz, CDCl3) δ 5.60 (s, 1H), 2.90 (dt, J = 16.4, 6.3 Hz, 2H), 2.32 (dt, J = 16.3, 6.0 Hz, 2H), 2.04 (s, 15H), 1.79 - 1.66 (m, 2H), 1.67 (s, 6H), 1.64 - 1.54 (m, 2H).

[0236]

[0237] Synthesis Example 2-2

[0238] (Cat 2-2)

[0239] Indene (1 eq) was dissolved in THF (0.3 M), and n-BuLi (1.05 eq) was slowly added dropwise at -25°C, followed by stirring at room temperature for 3 hours. Afterwards, CH3-I (1.05 eq) was added at -10°C, and stirred overnight at room temperature, worked up with water, and dried to obtain 3-MethylIndene. 3-MethylIndene (1 eq) thus synthesized was dissolved in THF (0.3 M), and n-BuLi (1.05 eq) was slowly added dropwise at -25°C, followed by stirring at room temperature for 3 hours. Afterwards, tert-butoxyhexyl-I (1.05 eq) was added at -10°C, stirred overnight at room temperature, worked up using water, and dried to obtain 1-methyl-3-(tert-butoxyhexyl)-Indene.

[0240]

[0241] Preparation of transition metal compounds

[0242] The above-mentioned ligand was dissolved in Ether (0.3 M), n-BuLi (1.05 eq) was added at -25°C, and stirred at room temperature for 3 hours. In a glove box, PMCpZrCl3 (Pentamethylcyclopentadienylzirconium trichloride) (1 eq) was prepared in another flask, added to the ligand-Li flask using a cannula at -25°C, and washed and added using Ether (1.0 M).

[0243] Upon completion of the reaction, the solvent was vacuum-dried, DCM was reintroduced, LiCl was removed through a filter, the filtrate was vacuum-dried, and slurry was formed using hexane. The resulting solid was then filtered and vacuum-dried to obtain a solid metallocene compound intermediate.

[0244]

[0245] In a glove box, the above metallocene compound intermediate was placed in a mini parr, and 5 mol% of Pd / C (10 wt%) was added. A magnetic bar was inserted here and moved outside the glove box using a closing system. DCM (0.5 M) was added to this parr, and H2 gas (10 barg) was added. After repeating the vent-charge cycle three times, the mixture was placed in a 40°C oil bath and stirred. When the pressure of the parr decreased below 5 barg, the previous charging process was repeated, and the reaction was continued until there was no more consumption of H2 gas. When the reaction was complete, the remaining H2 gas was vented and replaced with Ar gas. After cooling to room temperature, the mixture was filtered using a cannula, and the filtrate was vacuum-dried. The dried filtrate was slurried using hexane, and this was filtered to obtain a solid transition metal compound (Cat 2-2).

[0246] 1 H NMR (500 MHz, CDCl3) δ 5.57 (s, 1H), 3.31 (t, J = 6.7 Hz, 2H), 2.95 - 2.85 (m, 2H), 2.37 - 2.28 (m, 2H), 2.18 - 2.03 (m, 2H), 2.02 (s, 15H), 1.96 - 1.88 (m, 1H), 1.82 - 1.77 (m, 1H), 1.75 (s, 3H), 1.71 - 1.55 (m, 3H), 1.53 - 1.36 (m, 4H), 1.36 - 1.20 (m, 3H), 1.18 (s, 9H).

[0247]

[0248] Synthesis Example 2-3

[0249] (Cat 2-3)

[0250] Preparation of ligands

[0251] Indene (1 eq) was dissolved in THF (0.3 M), n-BuLi (1.05 eq) was slowly added dropwise at -25°C, and the mixture was stirred at room temperature for 3 hours. After that, CH3-CH2-I (1.05 eq) was added at -10°C, and the mixture was stirred overnight at room temperature, worked up with water, and dried to obtain 3-Ethyl-Indene.

[0252]

[0253] Preparation of transition metal compounds

[0254] The above-mentioned ligand was dissolved in Ether (0.3 M), n-BuLi (1.05 eq) was added at -25°C, and stirred at room temperature for 3 hours. In a glove box, PMCpZrCl3 (Pentamethylcyclopentadienylzirconium trichloride) (1 eq) was prepared in another flask, added to the ligand-Li flask using a cannula at -25°C, and washed and added using Ether (1.0 M).

[0255] Upon completion of the reaction, the solvent was vacuum-dried, DCM was reintroduced, LiCl was removed through a filter, the filtrate was vacuum-dried, and slurry was formed using hexane. The resulting solid was then filtered and vacuum-dried to obtain a solid metallocene compound intermediate.

[0256] In a glove box, the above metallocene compound intermediate was placed in a mini parr, and 5 mol% of Pd / C (10 wt%) was added. A magnetic bar was inserted here and moved outside the glove box using a closing system. DCM (0.5 M) was added to this parr, and H2 gas (10 barg) was added. After repeating the vent-charge cycle three times, the mixture was placed in a 40°C oil bath and stirred. When the pressure of the parr decreased below 5 barg, the previous charging process was repeated, and the reaction was continued until there was no more consumption of H2 gas. When the reaction was complete, the remaining H2 gas was vented and replaced with Ar gas. After cooling to room temperature, the mixture was filtered using a cannula, and the filtrate was vacuum-dried. The dried filtrate was slurried using hexane, and this was filtered to obtain a solid transition metal compound (Cat 2-3).

[0257] 1 H NMR (500 MHz, CDCl3) δ 5.60 (d, J = 2.7 Hz, 2H), 5.20 (d, J = 2.7 Hz, 2H), 2.83 - 2.71 (m, 2H), 2.49 - 2.36 (m, 3H), 2.21 (dd, J = 15.1, 7.6 Hz, 1H), 2.01 (s, 15H), 1.98 - 1.80 (m, 2H), 1.66 - 1.51 (m, 2H), 1.03 (t, J = 7.6 Hz, 3H).

[0258]

[0259] Synthesis Example 3

[0260] (Cat 3)

[0261] 2-Methyl-4-(4-tert-butyl-phenyl)-indene (1 eq.) was dissolved in MTBE (0.3 M), and n-BuLi (1.05 eq.) was slowly added dropwise to the resulting solution at -25°C, followed by stirring at room temperature for 3 hours. (t-BuOHex)MeSiCl2 (1.05 eq.) was added to the resulting reaction mixture at -10°C, and stirred at room temperature overnight to prepare a solution containing a mono-Si compound.

[0262] In another stirrer, 2-isopropy-4-(4-t-butyl-phenyl)-indene (1 eq) was dissolved in MTBE (0.3 M), and n-BuLi (1.05 eq) was slowly added dropwise to the resulting solution at -25°C, followed by stirring at room temperature for 3 hours. CuCN (2 mol%) was added to the resulting reaction mixture, stirred for 30 minutes, and then the mono-Si compound-containing solution prepared above was added. The mixture was stirred overnight at room temperature, worked up with water, and dried to obtain the ligand.

[0263] The above ligand was dissolved in toluene / ether (2 / 1 volume ratio, 0.53 M), and n-BuLi (2.05 equivalents) was added to the resulting solution at -25°C, followed by stirring at room temperature for 5 hours to prepare a lithiated ligand.

[0264] In a separate flask, a slurry prepared by mixing ZrCl4 (1 equivalent) with toluene (0.17 M) was added to the lithiated ligand and stirred overnight at room temperature. Upon completion of the reaction, the solvent was vacuum-dried, and DCM was added to the dried product, which was filtered to remove LiCl. The filtrate was vacuum-dried, and DCM and hexane were added to recrystallize at room temperature. The resulting solid was then filtered and vacuum-dried to obtain a solid transition metal compound (Cat 3).

[0265] 1H NMR (500MHz, CDCl3, 7.26ppm): 0.89 (3H, t), 1.08 (2H, m), 1.20 (9H, s), 1.35 (24H, s,m), 1.51 (2H, m), 1.61 (2H, m), 1.66 (2H, m), 1.88 (2H, m), 2.25 (3H, s), 3.28 (1H, m), 3.38 (2H, t), 6.98 (1H, s), 7.02 (1H, s), 7.11 (2H, dq), 7.36 (2H, dd), 7.46 (4H, dd), 7.51 (1H, m), 7.60 (4.5H, m), 7.70 (0.5H, d).

[0266]

[0267] Synthesis Example 4

[0268] A transition metal compound (Cat 4) having the following structure was prepared using the same method as in Comparative Synthesis Example 2 of Korean Patent Publication No. 10-2022-0067494.

[0269] (Cat 4)

[0270]

[0271] Synthesis Example 5

[0272] (Cat 5)

[0273] We purchased and used product 447862 (Cas. No. 73364-10-0) from Sigma Aldrich.

[0274]

[0275] Synthesis Example 6

[0276] (Cat 6)

[0277] A transition metal compound having the above structure was prepared using the same method as Manufacturing Example 2-3 of Korean Patent Publication No. 10-2016-0029718.

[0278]

[0279] Synthesis Example 7

[0280] (Cat 7)

[0281] A transition metal compound having the above structure was prepared according to the method disclosed in J. Am. Chem. Soc. 2004, VOL. 126, No. 46, pp.15231-15244.

[0282]

[0283] <Catalyst Manufacturing>

[0284] Manufacturing Example 1

[0285] 2.0 kg of toluene and 1000 g of silica (SP2410, Grace Davision) were charged into a 20L SUS high-pressure reactor, and the reactor temperature was raised to 40°C while stirring. 5.4 kg of methylaluminoxane (10 wt% in toluene, Albemarle) was charged into the reactor, the temperature was raised to 70°C, and the reactor was stirred at about 200 rpm for about 12 hours. Thereafter, the reactor temperature was lowered to 40°C, and stirring was stopped. The reaction product was allowed to stand for about 10 minutes and then decantated. 2.0 kg of toluene was then charged into the reaction product, stirred for about 10 minutes, stopped, and the reactor was allowed to stand for about 30 minutes before decantation.

[0286] 2.0 kg of toluene was charged into the reactor, and then the compound (Cat 1) (20 mmol) prepared in Synthesis Example 1 as the first transition metal compound, the compound (Cat 2-1) (10 mmol) prepared in Synthesis Example 2-1 as the second transition metal compound, and 1000 mL of toluene were charged. The temperature of the reactor was raised to 85°C, and stirring was performed for approximately 90 minutes.

[0287] Afterwards, the temperature of the reactor was lowered to room temperature, stirring was stopped, the reaction product was allowed to stand for about 30 minutes, and the reaction product was decantated. Next, 3 kg of hexane was added to the reactor, and the hexane slurry solution was transferred to a 20 L filter dryer, the solution was filtered, and dried under reduced pressure at 50 °C for about 4 hours to obtain 1.5 kg of a hybrid metallocene catalyst.

[0288] (Cat 1) (Cat 2-1)

[0289]

[0290] Manufacturing Examples 2 to 4 and Comparative Manufacturing Examples 1 to 3

[0291] As described in Table 1 below, a hybrid supported metallocene catalyst was prepared in the same manner as in Preparation Example 1, except that the types of the first and second transition metal compounds were changed.

[0292]

[0293] Catalyst 1 Transition metal compound 2 Transition metal compound Mixing molar ratio Preparation example 1 Cat 1, 20 mmol Cat 2-1, 10 mmol 2:1 Preparation example 2 Cat 1, 50 mmol Cat 2-2, 10 mmol 5:1 Preparation example 3 Cat 1, 20 mmol Cat 2-3, 10 mmol 2:1 Preparation example 4 Cat 1, 60 mmol Cat 2-2, 10 mmol 6:1 Comparative Preparation example 1 Cat 3, 10 mmol Cat 4, 10 mmol 1:1 Comparative Preparation example 2 Cat 1, 20 mmol Cat 6, 10 mmol 2:1 Comparative Preparation example 3 Cat 1, 40 mmol Cat 7, 10 mmol 4:1

[0294] <Manufacturing of polyethylene>

[0295] Examples 1-1 to 5-1 and Comparative Example 1-1

[0296] A 140 L continuous polymerizer capable of performing an isobutene slurry loop process with a polymerization reactor and operating at a reaction velocity of approximately 7 m / s was prepared. The reactants required for polyethylene polymerization were continuously fed into the reactor as described in Table 2. The catalysts used in each polymerization reaction were those prepared in the manufacturing examples or comparative manufacturing examples described in Table 1, and the catalysts were mixed with the isobutene slurry and fed. Furthermore, the polymerization reaction was performed at a pressure of approximately 40 bar and a temperature of approximately 85°C, and other key conditions for the polymerization reaction are shown in Table 2 below.

[0297]

[0298] Comparative Example 2-1

[0299] EP2010 manufactured by LG Chem was used.

[0300]

[0301] Comparative Example 3-1

[0302] LF100A manufactured by LG Chem was used.

[0303]

[0304] Comparative Examples 4-1 and 5-1

[0305] A 140-liter continuous polymerization reactor capable of performing an isobutene slurry loop process and operating at a reaction velocity of approximately 7 m / s was prepared. The reactants required for polyethylene polymerization were continuously fed into the reactor as described in Table 2. The catalysts used in each polymerization reaction were those described in Table 1, and the catalysts were mixed with the isobutene slurry and fed. Furthermore, the polymerization reaction was performed at a pressure of approximately 40 bar and a temperature of approximately 85°C. Other key conditions for the polymerization reaction are shown in Table 2 below.

[0306]

[0307] Catalytic ethylene input (kg / hr)1-Hexene input 1 (wt%) hydrogen input 2 (ppm)Activity (kgPE / kgSiO2·hr)Example 1-1 Manufacturing Example 126.413276.5Example 2-1 Manufacturing Example 22618385.2Example 3-1 Manufacturing Example 324.412305.5Example 4-1 Manufacturing Example 22520205.5Example 5-1 Manufacturing Example 42524345.5Comparative Example 1-1 Comparative Manufacturing Example 120.110.972.4Comparative Example 4-1 Comparative Manufacturing Example 224.016304.9Comparative Example 5-1 Comparative Manufacturing Example 323.7754.1

[0308] In Table 2 above, the activity (Activity, kgPE / kgSiO2·hr) was calculated as the ratio of the polymer weight (kgPE) produced per the catalyst weight (kg) used per unit time (hr).

[0309] Also, the 1-Hexene input amount (wt%) is calculated as a percentage of the 1-hexene input amount based on the total weight of monomers including ethylene and 1-hexene, and the hydrogen input amount (ppm) is calculated as a percentage of the total weight of monomers including ethylene and 1-hexene.

[0310]

[0311] Experimental Example 1

[0312] The physical properties of the polyethylene manufactured in the above examples and comparative examples were measured as follows, and the results are shown in Tables 3 and 4 below.

[0313] (1) Melt Index (MI) 2.16 ): Measured according to ASTM D1238 (Condition E, 190 ℃, 2.16 kg load).

[0314]

[0315] (2) Density: Measured according to ASTM D1505 standard.

[0316]

[0317] (3) Molecular weight distribution (MWD)

[0318] For the polyethylene according to the above examples and comparative examples, the weight average molecular weight (Mw, g / mol) and number average molecular weight (Mn, g / mol) were measured through gel permeation chromatography (GPC) analysis, and the molecular weight distribution (MWD, Mw / Mn) was obtained by dividing the weight average molecular weight measured above by the number average molecular weight.

[0319] Specifically, the gel permeation chromatography (GPC) device is Polymer Char GPC-IR. ® The device was used, and a Polymer Laboratories PLgel MIX-B 300 mm long 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. Each sample of polyethylene manufactured in the examples and comparative examples was analyzed using a GPC analysis device (Polymer Char GPC-IR ® ) was dissolved in 1,2,4-trichlorobenzene containing 0.03% BHT at 160℃ for 3 hours, pretreated, and then prepared at a concentration of 16 mg / 8 mL and supplied in an amount of 200 μL. The values ​​of Mw and Mn were calculated using a calibration curve formed using polystyrene standard specimens. The weight-average molecular weights of the polystyrene standard specimens were 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.

[0320]

[0321] (4) Analysis of crystal distribution and molecular weight distribution

[0322] Cross fraction chromatography (CFC) analysis was performed on the polyethylene manufactured in the above examples and comparative examples using the following method.

[0323]

[0324] [Cross-fractionation chromatography measurement conditions (including TREF and GPC analysis)]

[0325] - Analysis equipment: Polymer Char CFC - 7890B (G3440D)

[0326] (Detector: Integrated Detector IR5 MCT)

[0327] - Sample preparation and loading: 32 mg of polyethylene manufactured in the above examples or comparative examples was placed in a 10 mL vial and placed in an autosampler, 8 mL of 1,2,4-trichlorobenzene (TCB) was added, dissolved at 160°C for 90 minutes, and stabilized at 140°C for 20 minutes. After nitrogen purge, extraction was performed and loaded onto a temperature rising elution fractionation column (TREF column).

[0328] - Crystallization: The temperature of the sample previously loaded onto the TREF column was adjusted to 140℃, then cooled from 140℃ to 35℃ at a rate of 0.5℃ / min and maintained for 15 minutes.

[0329] The detailed conditions for the above stabilization and crystallization are as follows:

[0330]

[0331]

[0332] - Temperature Rising Elution Fractionation (TREF) Analysis: The previously crystallized sample was heated from 35°C to 120°C at a rate of 1°C / min to the fraction temperature shown below, then fixed. The concentrations of the fractions eluted at that temperature for 5 minutes were measured. A TREF analysis graph was derived from the concentration measurement results.

[0333] From the TREF graph, the content ratio of the polymer fraction eluted in the region of elution temperature exceeding 35℃ and less than 60℃ based on the total weight of the entire eluted fraction (35℃ <Te<60℃), 용리 온도 30℃ 이상이고 60℃ 미만의 영역에서 용출되는 중합체 분획의 함량 비율(30℃≤Te<60℃), 용리 온도 60℃ 이상이고 80℃ 미만의 영역에서 용출되는 중합체 분획의 함량 비율(60℃≤Te<80℃), 그리고 용리 온도 80℃ 이상의 영역에서 용출되는 중합체 분획의 함량 비율(80℃≤Te)을 각각 산출하였다(중량%).

[0334] <fraction temperature>

[0335] 35℃ / 40℃ / 43℃ / 46℃ / 49℃ / 52℃ / 55℃ / 58℃ / 61℃ / 64℃ / 67℃ / 70℃ / 73℃ / 76℃ / 79℃ / 82℃ / 85℃ / 88℃ / 91℃ / 94℃ / 97℃ / 100℃ / 105℃ / 120℃

[0336]

[0337] <Measurement conditions>

[0338]

[0339]

[0340] - GPC analysis: The fractions eluted for each temperature range in the previous TREF analysis were analyzed using a GPC device (Polymer Char GPC-IR) ®) After moving to the GPC Column equipped with me, GPC analysis is performed according to the following conditions, and the region where the elution temperature is over 35℃ and less than 60℃ (35℃ <Te<60℃)에서 용출되는 중합체의 중량평균 분자량(Mw)을 측정하였다.

[0341]

[0342] <Sample Preparation>

[0343] The polyethylene fraction is pretreated by dissolving it in 1,2,4-trichlorobenzene at 160°C for 10 hours, and then prepared at a concentration of 10 mg / 10 mL, and supplied in an amount of 200 μL.

[0344] <GPC 분석 조건>

[0345] GPC Device: Polymer Char GPC-IR ®

[0346] GPC Column: Polymer Laboratories PLgel MIX-B 300 mm long column

[0347] Measurement temperature: 160℃

[0348] Solvent: 1,2,4-Trichlorobenzene

[0349] Flow rate: 1 mL / min

[0350] Standard specimen: Polystyrene standard specimen

[0351] (Weight average molecular weight of polystyrene standard specimens: 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, 10000000 g / mol)

[0352]

[0353] <Measurement conditions>

[0354]

[0355]

[0356] A graph showing the relationship between the elution temperature (Te) (℃) and the elution amount (dW / dT) derived from the TREF analysis results of CFCs for polyethylene of Examples 1-1 to 5-1 is shown in Fig. 4, and a graph showing the relationship between the elution temperature (Te) (℃) and the elution amount (dW / dT) derived from the TREF analysis results of CFCs for polyethylene of Comparative Examples 1-1 to 5-1 is shown in Fig. 5.

[0357]

[0358]

[0359]

[0360]

[0361]

[0362] Experimental Example 2

[0363] After measuring the rheological properties of the polyethylene manufactured in Examples 1-1 to 5-1 and Comparative Examples 1-1 to 5-1, the relaxation time spectrum was analyzed using the results, and the relaxation spectrum index (RSI) was obtained according to the method proposed by Wasserman (S,.H.Wasserman ANTEC 1997, 55, 1129).

[0364] In addition, using the above rheological property measurement results, the ER (Polydispersity at the High MW) and PDR (overall polydispersity) of the polyethylene of the examples and comparative examples were obtained, respectively.

[0365]

[0366] (1) Sample manufacturing

[0367] For each of the polyethylenes manufactured in the above examples and comparative examples, samples for measuring rheological properties were manufactured by compression molding at 182°C for 3 minutes.

[0368] Specifically, the polyethylene of the examples and comparative examples was melted at 182°C under a pressure of 2 bar for 1 minute, then a pressure of 100 bar was additionally applied for 2 minutes, and quenched in a cooling press to manufacture a press mold sample in the shape of a disk with a thickness of 2 mm x a diameter of 25.4 mm.

[0369] Meanwhile, in the preparation of the above samples, since the polyethylene of Examples 1 to 3 and Comparative Examples 6, 7, and 8 is in powder form, in order to easily load it onto a rheometer and minimize sample deterioration or crosslinking during measurement, 1200 ppm of an antioxidant (Songnox 1076 (Songwon): Songnox 1680 (Songwon) = 1:2 weight ratio) was added and mixed based on the total weight of polyethylene, and pelletized by extrusion at an extrusion temperature of 190°C at an extrusion rate of 35 kg / hr using a twin screw extruder (TEK 30 MHS, manufactured by SMPLATECH CO., diameter 32 pi, L / D = 40). However, for samples that may already contain an antioxidant and processing aid during commercial pelletization, such as the polyethylene of Comparative Example 3, an antioxidant was not added.

[0370]

[0371] (2) Measurement of rheological properties

[0372] The storage modulus (G') and loss modulus (G") of the polyethylene of the examples and comparative examples were measured in frequency sweep mode using a rotational rheometer (ARES-G2 Rheometer, manufactured by TA Instruments), respectively.

[0373] Specifically, the test chamber of the rheometer was purged with nitrogen to minimize polyethylene degradation, and the rheometer was preheated to an initial temperature of 190°C. After sample loading and oven thermal equilibration, the sample prepared above was placed between the parallel plates of the rheometer (plate diameter: 25.4 mm, gap between plates: 2 mm) and pressed to a thickness of 2.0 mm. Vacuum shear flow was applied at a strain of 5% over each frequency range of 0.05 to 500 rad / s under a nitrogen atmosphere. At this time, the strain was kept within 5% to satisfy the linear viscoelasticity condition. A total of 8 minutes elapsed between the time the sample was inserted between the plates and the start of the frequency sweep (0.03-100 rad / s), and the measurements were performed at 190°C. Meanwhile, a new sample was used at each temperature, and nitrogen (N2) was circulated within the test chamber for each measurement.

[0374] Through the above measurements, the storage modulus (G') and loss modulus (G") for frequency (ω) were obtained.

[0375] From the results obtained from the above rheological property measurement results, a graph showing the relationship between the loss elastic modulus (G") and the storage elastic modulus (G') for the polyethylene of Examples 1-1 to 5-1 and Comparative Examples 1-1 to 5-1 was derived and shown in Fig. 6.

[0376]

[0377] (3) ER and PDR measurements

[0378] Using the rheological property measurement results of the above (2), the ER (Polydispersity at the High MW) and PDR (overall polydispersity) for the polyethylene of the examples and comparative examples were obtained, respectively, by the method described in the literature “New measures of polydispersity from rheological data on polymer melts”, Journal of Appied Polymer Science, vol. 57, 1605-1626 (1995).

[0379] Specifically, using the storage elastic modulus (G') and loss elastic modulus (G") obtained as the measurement results in (2) above, the graph was plotted as in Fig. 6 with Log(G") as the X-axis and log (G') as the Y-axis, and the plotted graph was curve-fitted using data analysis software (Origin Pro). As a result, the following linear relationship (5) was obtained.

[0380] logG' = k1+ k2log G" (5)

[0381] In the above mathematical equation, k1 and k2 are constants for curve fitting.

[0382] Next, as in the following mathematical expression 4, G" ref ER was obtained by interpolating the corresponding G' value.

[0383] [Equation 4]

[0384]

[0385] In the above mathematical formula 4,

[0386] C1 is a constant, 1.781x10 -3 And,

[0387] G' is the storage modulus of polyethylene (dyne / cm 2 ) and

[0388] G" refis the loss modulus of polyethylene, a small elastic modulus value corresponding to the low frequency range, 5000 dyne / cm 2 am.

[0389] Minimum G" value is 5000 dyne / cm 2 If it is larger, extrapolate to obtain ER.

[0390] Additionally, PDR (Overall Polydispersity) was calculated according to the following mathematical equation 5.

[0391] [Equation 5]

[0392]

[0393] In the above mathematical expression 5, η*1, η*2, and η*3 are the reference complex modulus G, respectively. * ref1 , G * ref2 , and G * ref3 As the complex viscosity in , G * ref1 =1.95x10 4 dyn / cm 2 And, G * ref2 = (G * ref1 G * ref3 ) 1 / 2 , and for linear polymers, log10(G * ref3 / G * ref1 )=2 were used as the standard to obtain η*1, η*2, and η*3.

[0394] In addition, the complex elastic modulus (G) obtained from the rheological property measurement results for the polyethylene of Examples 1-1 to 5-1 and Comparative Examples 1-1 to 5-1 * ) and the complex viscosity (η*) are shown in Fig. 7.

[0395]

[0396] (4) Relaxation time spectrum analysis

[0397] Based on the rheological property measurement results of (2) above, the dynamic modulus G'(ω) and G"(ω) were determined as a function of frequency (ω), respectively.

[0398] (3)

[0399] (4)

[0400] In the above mathematical equations (3) and (4), G'(ω) is the storage modulus, G"(ω) is the loss modulus. In addition, N is the number of modes in the mode distribution of the relaxation time spectrum, ω is the frequency (rad / s), and τ i is the discrete relaxation time (s), and G i is the elastic modulus (dyne / cm) corresponding to the relaxation time. 2 )am.

[0401] In addition, after calculating the mode distribution of the relaxation spectrum using IRIS rheological software (IRIS Development), the first moment of the distribution (G I ) and the second moment (G II ) was obtained according to the following mathematical formula.

[0402] (i)

[0403] (ii)

[0404] In the above mathematical equations (i) and (ii), N is the number of modes in the mode distribution of the relaxation time spectrum, and τ i is the relaxation time (s), and G i is the elastic modulus (dyne / cm) corresponding to the relaxation time. 2 )am.

[0405] In addition, using the values ​​measured above and the relaxation time spectrum analysis results, the zero shear viscosity (η) is calculated according to the following mathematical equation 6. 0 ) (Pa·s) was obtained.

[0406] [Equation 6]

[0407]

[0408] In the above mathematical expression 6, N is the number of modes in the mode distribution of the relaxation time spectrum, and τ i is the relaxation time (s), and G i is the elastic modulus (dyne / cm) corresponding to the relaxation time. 2 )am.

[0409] The results are shown in Tables 5 and 6 below.

[0410]

[0411] Unit Example 1-1 Example 2-1 Example 3-1 Example 4-1 Example 5-1 ERdyn / cm 2 1.181.451.541.721.42PDR-11.35.610.413.97.2η 0 Pa·s9,2349,58813,01713,44011,970

[0412]

[0413] Unit Comparison Example 1-1 Comparison Example 2-1 Comparison Example 3-1 Comparison Example 4-1 Comparison Example 5-1 ERdyn / cm 2 0.132.041.190.913.13PDR-2.217.89.96.749.2η 0 Pa·s7,33713,8129,0018,84328,790

[0414]

[0415] Film Manufacturing

[0416] A film was manufactured using the polyethylene manufactured in Examples 1-1 to 5-1 or Comparative Examples 1-1 to 5-1, using the following method.

[0417]

[0418] Examples 1-2 to 5-2, Comparative Examples 1-2 to 5-2

[0419] Based on the total weight of the polyethylene manufactured in Examples 1-1 to 5-1 or Comparative Examples 1-1 to 5-1, 1200 ppm of an antioxidant (Songnox 1076 (Songwon): Songnox 1680 (Songwon) = 1:2 in weight ratio) was added and mixed, and a twin screw extruder (TEK 30 MHS, manufactured by SMPLATECH CO., diameter 32 pi, L / D = 40) was used to extrude at an extrusion temperature of 190°C at an extrusion rate of 35 kg / hr, thereby manufacturing a composition for forming a pellet-shaped film weighing about 18 kg.

[0420] A film was manufactured by inflation molding the film-forming composition manufactured above under the following film extrusion conditions.

[0421] <Film forming conditions>

[0422] Single Screw Extruder (Eugene Engineering Single Screw Extruder, Blown Film M / C, 50 pi, L / D=32)

[0423] Melting temperature (or extrusion temperature): 185℃

[0424] Die Gap: 2.0mm

[0425] Die diameter: 120mm

[0426] Blown-Up Ratio: 2.5

[0427] Maintain Frost Line Height at 200~250mm

[0428] Sample extrusion rate: 300~500g / min

[0429] Cooling: Uses dual air-ring

[0430] Film thickness: 50㎛

[0431]

[0432] Experimental Example 3

[0433] For the films manufactured in Examples 1-2 to 5-2 and Comparative Examples 1-2 to 5-2, the drop impact strength, heat seal strength, sealing initiation temperature (SIT), and hot-tack strength were measured using the following methods.

[0434]

[0435] (1) Dart drop impact strength

[0436] For the films of the examples and comparative examples manufactured above, the drop impact strength was measured according to the ASTM D1709 [Method A] standard, and the average value was taken by measuring at least 5 sets (20 times / 1 set) per film sample.

[0437]

[0438] (2) Heat seal strength(N / 25.4mm)

[0439] According to ASTM F 1921, when the sealing strength was measured at each temperature at 5℃ intervals between 60℃ and 130℃ using a J&B Hot tack tester (Hot tacker 5000) under the conditions of a sealing time of 0.5 seconds, a sealing pressure of 0.3 MPa, a delay time of 30.0 seconds, and a tensile speed of 200 mm / sec, the highest strength was determined as the heat seal strength (N / 25.4 mm).

[0440] The measurement results are shown in Fig. 8.

[0441]

[0442] (3) Sealing initiation temperature (SIT)

[0443] According to ASTM F 1921, when the seal strength was measured at each temperature at 5℃ intervals between 60℃ and 130℃ using a J&B Hot tack tester (Hot tacker 5000) under the conditions of a sealing time of 0.5 seconds, a sealing pressure of 0.3 MPa, a delay time of 30.0 seconds, and a tensile speed of 200 mm / sec, the temperature at which the heat seal strength reached 2 N / 25.4 mm was defined as the seal initiation temperature (SIT).

[0444]

[0445] (4) Hot-tack strength (N / 25.4mm)

[0446] In addition, according to ASTM F 1921, when the tack strength was measured at each temperature at intervals of 5℃ between 60℃ and 130℃ using a J&B Hot tack tester (Hot tacker 5000) under the conditions of a sealing time of 0.5 seconds, a sealing pressure of 0.3 MPa, a delay time of 0.1 seconds, and a tensile speed of 200 mm / sec, the highest strength measured was taken as the hot-tack strength (N / 25.4 mm).

[0447] Meanwhile, in the present invention, in the unit of heat seal strength and hot-tack strength, N / 25.4 mm, “25.4 mm” means the width of the film sample for measuring sealing.

[0448] The results are shown in Tables 7, 8, and Fig. 9 below.

[0449]

[0450] Film properties (50㎛ thickness) Unit Example 1-2 Example 2-2 Example 3-2 Example 4-2 Example 5-2 Drop impact strength gf 1,36 39 72 1,07 0 7 33 1,12 3 SIT ℃ 8 6.5 8 0.5 8 1.5 7 0.5 8 1.5 Hot-tack Strength N / 25.4 mm 4.0 3 4.1 5 3.7 7 4.4 8 4.4 9

[0451]

[0452] Film properties (50㎛ thickness) Unit Comparison Example 1-2 Comparison Example 2-2 Comparison Example 3-2 Comparison Example 4-2 Comparison Example 5-2 Drop impact strength gf 1,200 527 > 1,900 1,204 448 SIT℃ 10 2 10 0.56 9.0 10 1.0 1 1 5.0 Hot-tack Strength N / 25.4 mm 3.0 5 2.4 2 2.8 9 2.3 8 2.14

[0453]

[0454] As a result of the experiment, the film of the example had a sealing initiation temperature (SIT) of 90°C or less and a hot-tack strength of 3 N / 25.4 mm or more, showing excellent low-temperature sealing and hot-tack properties compared to the film of the comparative example. In addition, the film of the example showed a high drop impact strength of 900 gf or more.

[0455] Meanwhile, the film of Comparative Example 1-2 exhibited significantly reduced low-temperature sealing properties due to the crystal characteristics of polyethylene having a low content of polymer fractions eluting at a dissolution temperature of 30°C or higher and less than 60°C.

[0456] In addition, the films of Comparative Examples 2-2 and 5-2 had significantly deteriorated low-temperature sealing properties and drop impact strength properties due to the crystalline properties of polyethylene and the wide molecular weight distribution properties, which had a low content of polymer fractions eluting at a dissolution temperature of 30°C or higher and less than 60°C, and Comparative Examples 2 and 4 also exhibited low Hot-tack Strength of less than 3 N / 25.4 mm.

[0457] In addition, Comparative Example 3-2 showed excellent low-temperature sealing properties and drop impact strength, but exhibited significantly reduced rigidity due to the crystal properties of polyethylene in which the content of the polymer fraction eluted at an elution temperature of 80°C or higher was excessively low.

[0458] In addition, Comparative Example 4-2 shows the crystal distribution characteristics of polyethylene having a high content of polymer fraction eluted at an elution temperature of 80°C or higher, and also at an elution temperature of 35°C. <Te<60℃에서의 용출되는 중합체 분획의 중량평균 분자량이 지나치게 큰 분자량 분포 특성으로 인해, 저하된 저온 실링 특성을 나타내었다.

[0459] From the above experimental results, it was confirmed that the polyethylene according to the present invention, which has controlled crystal distribution characteristics and molecular weight distribution characteristics, exhibits excellent low-temperature sealing characteristics and hot-tack characteristics, and also exhibits improved drop impact strength characteristics, rigidity, and molding processability in good balance with the sealing characteristics. In particular, the polyethylene according to the present invention exhibits a viscosity of 0.915 g / cm 3 Compared to LLDPE with a low density of less than 0.915 g / cm 3 Despite the relatively high density, it exhibited superior hot-tack characteristics.

Claims

1. Polyethylene satisfying the conditions (a1) to (a3): (a1) Density measured according to ASTM D1505: 0.912 to 0.925 g / cm 3 (a2) Molecular weight distribution: 2.50 to 5.00 (a3) When analyzing temperature-increasing elution fractions by cross-fraction chromatography, based on the total weight of polyethylene, (a3-1) The content of the polymer fraction eluted at an elution temperature of 80°C or higher is 30.0 to 55.0 wt%, (a3-2) The content of the polymer fraction eluted at a dissolution temperature of 60°C or higher and less than 80°C is 10.0 to 50.0 wt%, and (a3-3) The content of the polymer fraction eluted at a dissolution temperature of 30°C or higher and less than 60°C is 10.0 to 35.0 wt%.

2. In paragraph 1, Polyethylene, wherein the polymer eluting at a temperature higher than 35°C and less than 60°C has a weight average molecular weight of 60,000 to 190,000 g / mol when subjected to temperature-increasing elution fractionation analysis of cross-fractionation chromatography and gel permeation chromatography analysis.

3. In paragraph 1, Polyethylene, wherein, in a temperature rising elution fractionation analysis of cross-fraction chromatography, the content of a polymer fraction eluting at an elution temperature exceeding 35°C and less than 60°C is 5.0 to 30.0 wt% based on the total weight of polyethylene.

4. In paragraph 1, The above polyethylene is a polyethylene having a melting index of 0.50 to 5.00 g / 10 min, measured at a temperature of 190 ℃ and a load of 2.16 kg according to ASTM D1238.

5. In paragraph 1, The above polyethylene has an ER (Polydispersity at the High MW) of 0.10 to 2.00 dyn / cm, calculated according to the following mathematical formula 4. 2 In, polyethylene: [Equation 4] In the above mathematical formula 4, C1 is a constant, 1.781x10 -3 And, G' is the storage modulus of polyethylene (dyne / cm 2 ) and G"ref is the loss modulus of polyethylene, 5000 dyne / cm 2 am.

6. In paragraph 1, The above polyethylene is polyethylene having an overall polydispersity (PDR) of 2.5 to 20.0 calculated according to the following mathematical formula 5: [Equation 5] In the above mathematical expression 5, η*1, η*2, and η*3 are the reference complex modulus G, respectively. * ref1 , G * ref2 , and G * ref3 As the complex viscosity in , G * ref1 =1.95x10 4 dyne / cm 2 And, G * ref2 =(G * ref1 G * ref3 ) 1 / 2 , and log10(G * ref3 / G * ref1 ) is calculated based on 2.

7. In paragraph 1, The above polyethylene has a zero shear viscosity (η) calculated according to the following mathematical formula 6 0 ) of 6,000 to 20,000 Pa·s, polyethylene: [Equation 6] In the above mathematical expression 6, N is the number of modes, and G i is the elastic modulus (dyne / cm) corresponding to the relaxation time. 2 ), and τ i is the relaxation time (s).

8. In paragraph 1, The above polyethylene is a copolymer of ethylene and alpha-olefin.

9. A film containing polyethylene according to paragraph 1.

10. In paragraph 9, A film having a sealing initiation temperature (SIT) of 90.0°C or less, measured according to ASTM F 1921, when the film thickness is 45 to 55 μm.

11. In paragraph 9, A film having a hot-tack strength of 3.00 N / 25.4 mm or more, measured according to ASTM F 1921, when the film thickness is 45 to 55 ㎛.

12. In paragraph 9, A film having a drop impact strength of 500 gf or more as measured according to ASTM D 1709 when the film thickness is 45 to 55 ㎛.

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