Olefin polymer and method for producing the same

Abstract

The present invention relates to an olefin-based polymer and a production method thereof. The olefin-based polymer according to the embodiment of the present invention has a high melting temperature and crystallization temperature, and has excellent heat resistance as a resin. Therefore, the olefin-based polymer according to the embodiment of the present invention can be used for spout pouches for high-temperature liquid containers, etc.

Description

Technical Field

[0001] The present invention relates to an olefin polymer and a method for producing the same. Specifically, the present invention relates to an olefin polymer having excellent heat resistance and a method for producing the same.

Background Art

[0002] A metallocene catalyst, which is one of the catalysts used for polymerizing olefins, has a sandwich structure as a basic form, as a compound in which ligands such as cyclopentadienyl, indenyl, and cycloheptadienyl are coordinately bonded to a transition metal or a transition metal halogen compound.

[0003] Another catalyst used for polymerizing olefins, the Ziegler-Natta catalyst, has a metal component, which is an active site, dispersed on an inert solid surface, and the nature of the active sites is not uniform. In contrast, since the metallocene catalyst is a single compound having a certain structure, all the active sites are known as a single-site catalyst having the same polymerization characteristics. The polymer polymerized by such a metallocene catalyst has a narrow molecular weight distribution, a uniform comonomer distribution, and a higher copolymerization activity than the Ziegler-Natta catalyst.

[0004] On the one hand, linear low-density polyethylene (LLDPE) is produced by copolymerizing ethylene and α-olefin at low pressure using a polymerization catalyst. It has a narrow molecular weight distribution, short chain branches (SCBs) of a certain length, and generally no long chain branches (LCBs). Films made from linear low-density polyethylene, in addition to the characteristics of general polyethylene, have high breaking strength and elongation, and are excellent in tear strength, impact strength, etc. Therefore, they are widely used in stretch films, overlap films, etc., where it is difficult to apply conventional low-density polyethylene and high-density polyethylene.

[0005] However, in order to utilize olefin polymers produced by metallocene catalysts in spout pouches for high-temperature liquid containers, etc., excellent heat resistance is required.

Summary of the Invention

Problems to be Solved by the Invention

[0006] An object of the present invention is to provide an olefin polymer having excellent heat resistance. Another object of the present invention is to provide a method for producing the olefin polymer.

Means for Solving the Problems

[0007] According to one embodiment of the present invention, an olefin polymer is provided, having a density of 0.9 to 0.95 g / cm 3 , preferably 0.91 to 0.945 g / cm 3 and satisfying the following Mathematical Formulas 1a and 2a.

[0008] [Mathematical Formula 1a] 224.02×d - 86.257 < Tm

[0009] [Mathematical Formula 2a] 219.64×d - 95.767 < Tc

[0010] In the above formula, Tm is the melting temperature (°C), Tc is the crystallization temperature (°C), and d is the density of the olefin polymer (g / cm 3 ).

[0011] In a specific example of the present invention, the olefin polymer satisfies the following Formula 1b and Formula 2b.

[0012] [Formula 1b] Tm < 224.02×d - 82.257

[0013] [Formula 2b] Tc < 219.64×d - 91.767

[0014] In a specific example of the present invention, the olefin polymer may have (1) a density of 0.918 to 0.945 g / cm 3 , (2) a melt index (I 2.16 ) measured at 190°C under a load of 2.16 kg of 0.1 to 5.0 g / 10 min, (3) a ratio (melt flow ratio; MFR) of the melt index (I 21.6 ) measured at 190°C under a load of 21.6 kg to the melt index (I 2.16 ) measured under a load of 2.16 kg of 17 or more, (4) a melting temperature of 120°C or higher, and (5) a crystallization temperature of 107°C or higher.

[0015] In a specific example of the present invention, the olefin polymer may be produced by polymerizing an olefin monomer in the presence of a hybrid catalyst containing at least one first transition metal compound represented by the following Chemical Formula 1 and at least one second transition metal compound selected from a compound represented by the following Chemical Formula 2 and a compound represented by the following Chemical Formula 3.

[0016] [Chemical Formula]

[0017] [Chemical formula]

[0018] [Chemical formula]

[0019] In the above Chemical formula 1 to Chemical formula 3, M1 and M2 are different from each other and are each independently titanium (Ti), zirconium (Zr), or hafnium (Hf). X is each independently halogen, C 1-20 alkyl, C 2-20 alkenyl, C 2-20 alkynyl, C 6-20 aryl, C 1-20 alkyl C 6-20 aryl, C 6-20 aryl C 1-20 alkyl, or C 1-20 alkylamide. R1 to R 10 are each independently hydrogen, substituted or unsubstituted C 1-20 alkyl, substituted or unsubstituted C 2-20 alkenyl, substituted or unsubstituted C 6-20 aryl, substituted or unsubstituted C 1-20 alkyl C 6-20 aryl, substituted or unsubstituted C 6-20 aryl C 1-20 alkyl, substituted or unsubstituted C 1-20 heteroalkyl, substituted or unsubstituted C 3-20 heteroaryl, substituted or unsubstituted C 1-20 alkylamide, substituted or unsubstituted C 6-20 arylamide, substituted or unsubstituted C 1-20 alkylidene, or substituted or unsubstituted C 1-20 silyl, and R1 to R 10 are each independently such that adjacent groups are linked to form a substituted or unsubstituted saturated or unsaturated C 4-20 ring.

[0020] In a specific example of the present invention, M1 and M2 are different from each other and are zirconium or hafnium respectively, and X is a halogen or C 1-20 alkyl, and R1 to R 10 are each hydrogen, a substituted or unsubstituted C 1-20 alkyl, a substituted or unsubstituted C 1-20 alkenyl, or a substituted or unsubstituted C 6-20 aryl. In a preferred specific example of the present invention, M1 is hafnium, M2 is zirconium, and X may be chlorine or methyl.

[0021] In a preferred specific example of the present invention, the first transition metal compound is at least one of the transition metal compounds represented by the following chemical formulas 1-1 and 1-2, and the second transition metal compound may be at least one of the transition metal compounds represented by the following chemical formulas 2-1, 2-2, and 3-1.

[0022]

Chemical formula

[0023]

Chemical formula

[0024] In a specific example of the present invention, the molar ratio of the second transition metal compound to the first transition metal compound is in the range of 100:1 to 1:100.

[0025] In a specific example of the present invention, the catalyst may contain at least one cocatalyst selected from the group consisting of the compound represented by the following chemical formula 4, the compound represented by the following chemical formula 5, and the compound represented by the following chemical formula 6.

[0026]

Chemical formula

[0027] [Chemical formula]

[0028] [Chemical formula 6] [L-H] + [Z(A)4] - or [L] + [Z(A)4] -

[0029] In the chemical formula 4, n is an integer of 2 or more, and R a is a halogen atom, C 1-20 hydrocarbon group, or C substituted with halogen 1-20 hydrocarbon group, In the chemical formula 5, D is aluminum (Al) or boron (B), and R b , R c , and R d are each independently a halogen atom, C 1-20 hydrocarbon group, C substituted with halogen 1-20 hydrocarbon group, or C 1-20 alkoxy group, In the chemical formula 6, L is a neutral or cationic Lewis base, [L-H] + and [L] + are Bronsted acids, Z is a Group 13 element, and A is each independently a substituted or unsubstituted C 6-20 aryl group, or a substituted or unsubstituted C 1-20 alkyl group.

[0030] In a specific example of the present invention, the catalyst may further include a transition metal compound, a cocatalyst compound, or a carrier supporting both. In a preferred specific example of the present invention, the carrier may include at least one selected from the group consisting of silica, alumina, and magnesia.

[0031] Here, the total amount of the hybrid transition metal compound supported on the carrier is 0.001 to 1 mmole based on 1 g of the carrier, and the total amount of the cocatalyst compound supported on the carrier is 2 to 15 mmole based on 1 g of the carrier.

[0032] In a specific example of the present invention, the olefin polymer is a copolymer of an olefin monomer and an olefin comonomer. Specifically, the olefin monomer is ethylene, and the olefin comonomer may be at least one selected from the group consisting of propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene, 1-undecene, 1-dodecene, 1-tetradecene, and 1-hexadecene. Preferably, the olefin polymer is a linear low-density polyethylene in which the olefin monomer is ethylene and the olefin comonomer is 1-hexene.

[0033] According to one embodiment of the present invention, in the presence of a hybrid catalyst containing at least one first transition metal compound represented by the chemical formula 1 and at least one second transition metal compound selected from the compound represented by the chemical formula 2 and the compound represented by the chemical formula 3, an olefin monomer is polymerized to obtain an olefin polymer, and the density of the olefin polymer is 0.9 to 0.95 g / cm 3 , preferably 0.91 to 0.945 g / cm 3 , and a method for producing an olefin polymer that satisfies the following mathematical formulas 1a and 2a is provided.

[0034] [Mathematical formula 1a] 224.02 × d - 86.257 < Tm

[0035] [Mathematical formula 2a] 219.64 × d - 95.767 < Tc

[0036] In the above formulas, Tm is the melting temperature (°C), Tc is the crystallization temperature (°C), and d is the density of the olefin polymer (g / cm 3 ).

[0037] In a specific example of the present invention, the olefin polymer satisfies the following Mathematical Formulas 1b and 2b.

[0038] [Mathematical Formula 1b] Tm < 224.02×d - 82.257

[0039] [Mathematical Formula 2b] Tc < 219.64×d - 91.767

[0040] In a specific example of the present invention, the polymerization of the olefin monomer may be carried out by gas-phase polymerization. Specifically, the polymerization of the olefin monomer may be carried out in a gas-phase fluidized bed reactor. [Advantages of the Invention]

[0041] The olefin polymer according to an embodiment of the present invention is excellent in heat resistance and can be used for a spout pouch for a high-temperature liquid container or the like. In particular, the olefin polymer according to an embodiment of the present invention satisfies a specific relationship between the melting temperature and the crystallization temperature with respect to the density, and has a relatively high melting temperature and crystallization temperature at the same level of density. Therefore, at the time of polymerization of the olefin polymer, by changing the density according to its use, an olefin polymer that can be effectively applied to various fields such as adhesives, films, and packaging materials can be provided. [Brief Description of the Drawings]

[0042]

Figure 1

Figure 2

[0043] Hereinafter, the present invention will be described in more detail. Olefin polymer According to one embodiment of the present invention, an olefin polymer having a density of 0.9 to 0.95 g / cm 3 is provided, which satisfies the following Mathematical Formula 1a and Mathematical Formula 2a.

[0044] [Mathematical Formula 1a] 224.02×d - 86.257 < Tm

[0045] [Mathematical Formula 2a] 219.64×d - 95.767 < Tc

[0046] In the above formulas, Tm is the melting temperature (°C), Tc is the crystallization temperature (°C), and d is the density of the olefin polymer (g / cm 3 ).

[0047] In a specific example of the present invention, the olefin polymer satisfies the following Mathematical Formula 1b and Mathematical Formula 2b.

[0048] [Mathematical Formula 1b] Tm < 224.02×d - 82.257

[0049] [Mathematical Formula 2b] Tc < 219.64×d - 91.767

[0050] In a specific example of the present invention, the olefin polymer may (1) have a density of 0.918 to 0.945 g / cm 3 , (2) have a melt index (I 2.16 ) measured at 190 °C under a load of 2.16 kg of 0.1 to 5.0 g / 10 min, (3) have a ratio (melt flow ratio; MFR) of the melt index (I 21.6 ) measured at 190 °C under a load of 21.6 kg to the melt index (I 2.16 ) measured under a load of 2.16 kg of 17 or more, (4) have a melting temperature of 120 °C or higher, and (5) have a crystallization temperature of 107 °C or higher.

[0051] In a specific example of the present invention, the olefin polymer has a density of 0.9 to 0.95 g / cm 3 . Preferably, the density of the olefin polymer is 0.91 to 0.945 g / cm 3 , 0.91 to 0.93 g / cm 3 , 0.918 to 0.945 g / cm 3 , 0.918 to 0.942 g / cm 3 , or 0.915 to 0.925 g / cm 3 .

[0052] In a specific example of the present invention, the olefin polymer has a melt index (I 2.16 ) measured at a load of 2.16 kg at 190 °C of 0.1 to 5.0 g / 10 min. Preferably, the melt index of the olefin polymer measured at a load of 2.16 kg at 190 °C may be 0.3 to 4.0 g / 10 min, 0.5 to 3.5 g / 10 min, or 0.5 to 3.0 g / 10 min.

[0053] In a specific example of the present invention, the olefin polymer has a ratio (melt flow ratio; MFR) of the melt index (I 21.6 ) measured at a load of 21.6 kg at 190 °C to the melt index (I 2.16 ) measured at a load of 2.16 kg at 190 °C of 17 or more. Preferably, the MFR of the olefin polymer may be 20 or more, 22 or more, or 20 to 50.

[0054] In a specific example of the present invention, the olefin polymer has a melting temperature (melting temperature; T m ) of 118 °C or higher. Preferably, the melting temperature of the olefin polymer may be 120 °C or higher or 120 to 130 °C.

[0055] In a specific example of the present invention, the olefin polymer has a crystallization temperature (crystallization temperature; T c ) of 106 °C or higher. Preferably, the crystallization temperature of the olefin polymer may be 107 °C or higher or 107 to 117 °C.

[0056] The olefin-based polymer according to an embodiment of the present invention is produced by polymerizing an olefin-based monomer in the presence of a hybrid catalyst containing at least one first transition metal compound represented by the following chemical formula 1 and at least one second transition metal compound selected from the compounds represented by the following chemical formula 2 and the compounds represented by the following chemical formula 3.

[0057]

Chemical formula

[0058]

Chemical formula

[0059]

Chemical formula

[0060] In the above chemical formulas 1 to 3, M1 and M2 are different from each other and are each independently titanium (Ti), zirconium (Zr), or hafnium (Hf). Specifically, M1 and M2 may be different from each other and each may be zirconium or hafnium. Preferably, M1 may be hafnium and M2 may be zirconium.

[0061] X is each independently halogen, C 1-20 alkyl, C 2-20 alkenyl, C 2-20 alkynyl, C 6-20 aryl, C 1-20 alkyl C 6-20 aryl, C 6-20 aryl C 1-20 alkyl, C 1-20 alkylamide, or C 6-20 arylamide. Specifically, X may each be halogen or C 1-20 alkyl. Preferably, X may be chlorine or methyl.

[0062] R1 to R 10 are each independently hydrogen, substituted or unsubstituted C 1-20 alkyl, substituted or unsubstituted C 2-20 alkenyl, substituted or unsubstituted C 6-20 aryl, substituted or unsubstituted C 1-20 alkyl C 6-20 aryl, substituted or unsubstituted C 6-20 aryl C 1-20 alkyl, substituted or unsubstituted C 1-20 heteroalkyl, substituted or unsubstituted C 3-20 heteroaryl, substituted or unsubstituted C 1-20 alkylamide, substituted or unsubstituted C 6-20 arylamide, substituted or unsubstituted C 1-20 alkylidene, or substituted or unsubstituted C 1-20 silyl, where R1 to R 10 are each independently such that adjacent groups are linked to form a substituted or unsubstituted saturated or unsaturated C 4-20 ring. Specifically, R1 to R 10 are each hydrogen, substituted or unsubstituted C 1-20 alkyl, substituted or unsubstituted C 1-20 alkenyl, or substituted or unsubstituted C 6-20 aryl.

[0063] In specific examples of the present invention, M1 and M2 are different from each other and are each zirconium or hafnium, X is each halogen or C 1-20 alkyl, and R1 to R 10 are each hydrogen, substituted or unsubstituted C 1-20 alkyl, substituted or unsubstituted C 1-20 alkenyl, or substituted or unsubstituted C 6-20 aryl. In a preferred specific example of the present invention, M1 is hafnium, M2 is zirconium, and X may be chlorine or methyl.

[0064] In a preferred specific example of the present invention, the first transition metal compound is at least one of the transition metal compounds represented by the following chemical formulas 1-1 and 1-2, and the second transition metal compound may be at least one of the transition metal compounds represented by the following chemical formulas 2-1, 2-2, and 3-1.

[0065]

Chemical formula

[0066]

Chemical formula

[0067] In a specific example of the present invention, the molar ratio of the second transition metal compound to the first transition metal compound is in the range of 100:1 to 1:100. Preferably, the molar ratio of the second transition metal compound to the first transition metal compound is in the range of 50:1 to 1:50. Preferably, the molar ratio of the second transition metal compound to the first transition metal compound is in the range of 10:1 to 1:10.

[0068] In a specific example of the present invention, the catalyst may contain at least one cocatalyst compound selected from the group consisting of the compounds represented by the following chemical formula 4, the compounds represented by the following chemical formula 5, and the compounds represented by the following chemical formula 6.

[0069]

Chemical formula

[0070] In the above chemical formula 4, n is an integer of 2 or more, and R a is a halogen atom, C 1-20 hydrocarbon, or C substituted with halogen 1-20 hydrocarbon may be sufficient. Specifically, R a may be methyl, ethyl, n-butyl, or isobutyl.

[0071]

Chemical formula

[0072] In the formula (5), D is aluminum (Al) or boron (B), and R b , R c , and R d are each independently a halogen atom, a C 1-20 hydrocarbon group, a C 1-20 hydrocarbon group substituted with halogen, or a C 1-20 alkoxy group. Specifically, when D is aluminum (Al), R b , R c , and R d may each independently be methyl or isobutyl, and when D is boron (B), R b , R c , and R d may each be pentafluorophenyl.

[0073] [Chemical formula 6] [L-H] + [Z(A)4] - or [L] + [Z(A)4] -

[0074] In the formula (6), L is a neutral or cationic Lewis base, [L-H] + and [L] + are Bronsted acids, Z is a Group 13 element, and A is each independently a substituted or unsubstituted C 6-20 aryl group or a substituted or unsubstituted C 1-20 alkyl group. Specifically, [L-H] + may be a dimethylanilinium cation, [Z(A)4] - may be [B(C6F5)4] - , and [L] + may be [(C6H5)3C] + .

[0075] Specifically, examples of the compound represented by the chemical formula 4 include methylaluminoxane, ethylaluminoxane, isobutylaluminoxane, butylaluminoxane, etc., and methylaluminoxane is preferred, but it is not limited thereto.

[0076] Examples of the compound represented by the chemical formula 5 include trimethylaluminum, triethylaluminum, triisobutylaluminum, tripropylaluminum, tributylaluminum, dimethylchloroaluminum, triisopropylaluminum, tri-s-butylaluminum, tricyclopentylaluminum, tripentylaluminum, triisopentylaluminum, trihexylaluminum, trioctylaluminum, ethyldimethylaluminum, methyldiethylaluminum, triphenylaluminum, tri-p-tolylaluminum, dimethylaluminum methoxide, dimethylaluminum ethoxide, trimethylboron, triethylboron, triisobutylboron, tripropylboron, tributylboron, etc., and trimethylaluminum, triethylaluminum, and triisobutylaluminum are preferred, but it is not limited thereto.

[0077] Examples of the compound represented by the chemical formula 6 include triethylammonium tetraphenylboron, tributylammonium tetraphenylboron, trimethylammonium tetraphenylboron, tripropylammonium tetraphenylboron, trimethylammonium tetra(p-tolyl)boron, trimethylammonium tetra(o,p-dimethylphenyl)boron, tributylammonium tetra(p-trifluoromethylphenyl)boron, trimethylammonium tetra(p-trifluoromethylphenyl)boron, tributylammonium tetrapentafluorophenylboron, N,N-diethylanilinium tetraphenylboron, N,N-diethylanilinium tetrapentafluorophenylboron, diethylammonium tetrapentafluorophenylboron, triphenylphosphonium tetraphenylboron, trimethylphosphonium tetraphenylboron, triethylammonium tetraphenylaluminum, tributylammonium tetraphenylaluminum, trimethylammonium tetraphenylaluminum, tripropylammonium tetraphenylaluminum, trimethylammonium tetra(p-tolyl)aluminum, tripropylammonium tetra(p-tolyl)aluminum, triethylammonium tetra(o,p-dimethylphenyl)aluminum, tributylammonium tetra(p-trifluoromethylphenyl)aluminum, trimethylammonium tetra(p-trifluoromethylphenyl)aluminum, tributylammonium tetrapentafluorophenylaluminum, N,N-diethylanilinium tetraphenylaluminum, N,N-diethylanilinium tetrapentafluorophenylaluminum, diethylammonium tetrapenta-tetraphenylaluminum, triphenylphosphonium tetraphenylaluminum, trimethylphosphonium tetraphenylaluminum, tripropylammonium tetra(p-tolyl)boron, triethylammonium tetra(o,(p-dimethylphenyl)boron, tributylammonium tetra(p-trifluoromethylphenyl)boron, triphenylcarbonium tetra(p-trifluoromethylphenyl)boron, triphenylcarbonium tetrapentafluorophenylboron, and the like can be mentioned.

[0078] In a specific example of the present invention, the catalyst may further include a carrier that supports a transition metal compound, a cocatalyst compound, or both. Specifically, the carrier may support both the transition metal compound and the cocatalyst compound.

[0079] At this time, the carrier may contain a substance containing a hydroxy group on its surface. Preferably, a substance having a highly reactive hydroxy group and a siloxane group, which is dried and has the moisture removed from its surface, may be used. For example, the carrier may include at least one selected from the group consisting of silica, alumina, and magnesia. Specifically, silica dried at a high temperature, silica-alumina, silica-magnesia, and the like may be used as the carrier. Usually, these may contain oxide, carbonate, sulfate, and nitrate components such as Na2O, K2CO3, BaSO4, and Mg(NO3)2. Also, these may include carbon, zeolite, magnesium chloride, and the like. However, the carrier is not limited to these and is not particularly limited as long as it can support the transition metal compound and the cocatalyst compound.

[0080] The carrier may have an average particle size of 10 to 250 μm, preferably an average particle size of 10 to 150 μm, and more preferably 20 to 100 μm.

[0081] The volume of the fine pores of the carrier may be 0.1 to 10 cc / g, preferably 0.5 to 5 cc / g, and more preferably 1.0 to 3.0 cc / g.

[0082] The specific surface area of the carrier may be 1 to 1,000 m 2 / g, preferably 100 to 800 m 2It may also be in g, more preferably 200 to 600 m 2 It may also be in g.

[0083] In a preferred specific example of the present invention, the carrier may be silica. At this time, the drying temperature of the silica may be 200 to 900 °C. The drying temperature is preferably 300 to 800 °C, and more preferably 400 to 700 °C. When the drying temperature is less than 200 °C, there is too much moisture, so the moisture on the surface reacts with the promoter compound. When it exceeds 900 °C, the structure of the carrier may collapse.

[0084] The concentration of hydroxy groups in the dried silica may be 0.1 to 5 mmole / g, preferably 0.7 to 4 mmole / g, and more preferably 1.0 to 2 mmole / g. When the concentration of hydroxy groups is less than 0.1 mmole / g, the loading amount of the first promoter compound becomes low, and when it exceeds 5 mmole / g, there may be a problem that the catalyst component is inactivated.

[0085] The total amount of the transition metal compound supported on the carrier may be 0.001 to 1 mmole based on 1 g of the carrier. When the ratio of the transition metal compound to the carrier satisfies the above range, it shows appropriate supported catalyst activity and is advantageous in terms of maintaining the activity of the catalyst and economy.

[0086] The total amount of the promoter compound supported on the carrier may be 2 to 15 mmole based on 1 g of the carrier. When the ratio of the promoter compound to the carrier satisfies the above range, it is advantageous in terms of maintaining the activity of the catalyst and economy.

[0087] One or more carriers may be used. For example, both the transition metal compound and the promoter compound may be supported on one carrier, or the transition metal compound and the promoter compound may be respectively supported on two or more carriers. Also, only one of the transition metal compound and the promoter compound may be supported on the carrier.

[0088] As a method for supporting a transition metal compound and / or a cocatalyst compound that can be used in an olefin polymerization catalyst, a physical adsorption method or a chemical adsorption method may be used.

[0089] For example, the physical adsorption method includes a method of drying after bringing a solution in which a transition metal compound is dissolved into contact with a carrier, a method of drying after bringing a solution in which a transition metal compound and a cocatalyst compound are dissolved into contact with a carrier, or a method of producing a carrier on which a transition metal compound is supported by drying after bringing a solution in which a transition metal compound is dissolved into contact with a carrier, and separately, producing a carrier on which a cocatalyst compound is supported by drying after bringing a solution in which a cocatalyst compound is dissolved into contact with a carrier, and then mixing them.

[0090] The chemical adsorption method may include a method of first supporting a cocatalyst compound on the surface of a carrier and then supporting a transition metal compound on the cocatalyst compound, or a method of covalently bonding a functional group on the carrier surface (for example, in the case of silica, the hydroxy group (-OH) on the silica surface) and a catalyst compound.

[0091] In a specific example of the present invention, the olefin polymer may be a homopolymer of an olefin monomer or a copolymer of an olefin monomer and a comonomer. Preferably, the olefin polymer is a copolymer of an olefin monomer and an olefin comonomer.

[0092] Here, the olefin monomer is C 2-20 α-olefin, C 1-20 diolefin, C 3-20 cycloolefin, and C 3-20 at least one selected from the group consisting of cyclodiolefin.

[0093] For example, the olefin monomer may be ethylene, propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene, 1-undecene, 1-dodecene, 1-tetradecene, or 1-hexadecene, etc. The olefin polymer may be a homopolymer containing only one kind of the olefin monomer exemplified above, or a copolymer containing two or more kinds.

[0094] In an exemplary embodiment, the olefin polymer may be a copolymer in which ethylene and C 3-20 α-olefin are copolymerized. Preferably, the olefin polymer may be linear low-density polyethylene in which the olefin monomer is ethylene and the olefin comonomer is 1-hexene.

[0095] In this case, the content of ethylene is preferably 55 to 99.9% by weight, more preferably 90 to 99.9% by weight. The content of the α-olefin comonomer is preferably 0.1 to 45% by weight, more preferably 0.1 to 10% by weight.

[0096] Method for producing olefin polymer According to one embodiment of the present invention, there is provided a method for producing an olefin polymer, which includes a step of polymerizing an olefin monomer in the presence of a hybrid catalyst containing at least one first transition metal compound represented by the following Chemical Formula 1 and at least one second transition metal compound selected from the compound represented by the following Chemical Formula 2 and the compound represented by the following Chemical Formula 3 to obtain an olefin polymer.

[0097]

Chemical formula

[0098]

Chemical formula

[0099] [Chemical formula]

[0100] In the above chemical formula, M1, M2, X, and R1 to R 10 are the same as the descriptions in the item of the olefin-based polymer.

[0101] As described above, the olefin-based polymer produced by the production method according to an embodiment of the present invention has a density of 0.9 to 0.95 g / cm 3 and satisfies the following Mathematical Formulas 1a and 2a.

[0102] [Mathematical Formula 1a] 224.02×d - 86.257 < Tm

[0103] [Mathematical Formula 2a] 219.64×d - 95.767 < Tc

[0104] In the above formulas, Tm is the melting temperature (°C), Tc is the crystallization temperature (°C), and d is the density of the olefin-based polymer (g / cm 3 ).

[0105] In a specific example of the present invention, the olefin-based polymer satisfies the following Mathematical Formulas 1b and 2b.

[0106] [Mathematical Formula 1b] Tm < 224.02×d - 82.257

[0107] [Mathematical Formula 2b] Tc < 219.64×d - 91.767

[0108] In a specific example of the present invention, the olefin-based polymer (1) has a density of 0.918 to 0.945 g / cm 3 and (2) has a melt index (I 2.16 ) measured at a load of 2.16 kg at 190°C of 0.1 to 5.0 g / 10 min, and (3) has a melt index (I 21.6) and the melt flow ratio (MFR) with the melt index (I 2.16 ) measured under a load of 2.16 kg is 17 or more, (4) the melting temperature is 120°C or more, and (5) the crystallization temperature may be 107°C or more.

[0109] In a specific example of the present invention, the olefin polymer may be polymerized by, for example, polymerization reactions such as free radical, cationic, coordination, condensation, addition, etc., but is not limited thereto.

[0110] As one embodiment of the present invention, the olefin polymer may be produced by a gas phase polymerization method, a solution polymerization method, a slurry polymerization method, or the like. Preferably, the polymerization of the olefin monomer may be carried out by gas phase polymerization. Specifically, the polymerization of the olefin monomer may be carried out in a gas phase fluidized bed reactor.

[0111] When the olefin polymer is produced by a solution polymerization method or a slurry polymerization method, examples of solvents that can be used include C such as pentane, hexane, heptane, nonane, decane, and isomers thereof 5-12 aliphatic hydrocarbon solvents; aromatic hydrocarbon solvents such as toluene and benzene; hydrocarbon solvents substituted with chlorine atoms such as dichloromethane and chlorobenzene; and mixtures thereof, etc., but are not limited thereto.

[0112] Examples Hereinafter, the present invention will be described more specifically by way of examples. However, the following examples are merely for illustrating the present invention, and the scope of the present invention is not limited thereto.

[0113] Production Examples The transition metal compound of Chemical Formula 1-1 (bis(n-propylcyclopentadienyl)hafnium dichloride) and the transition metal compound of Chemical Formula 2-1 (bis(n-butylcyclopentadienyl)zirconium dichloride) were purchased from TCI and used without additional purification process.

[0114] 892 g of a toluene solution of 10% methylaluminoxane was added to 4.47 g of the transition metal compound of Chemical Formula 1-1 and 1.67 g of the transition metal compound of Chemical Formula 2-1, and the mixture was stirred at room temperature for 1 hour. The reaction solution after completion of the reaction was added to 200 g of silica (XPO-2402), and further 1.5 liters of toluene was added, and the mixture was stirred at 70 °C for 2 hours. The supported catalyst after completion of the loading was washed with 500 ml of toluene and dried overnight in vacuo at 60 °C to obtain 280 g of a powdered supported catalyst.

[0115] Examples 1 to 3 Using a gas-phase fluidized bed reactor, an ethylene / 1-hexene copolymer was produced in the presence of the supported catalyst obtained in Production Example 1. The ethylene partial pressure in the reactor was maintained at about 15 kg / cm 2 and the polymerization temperature was maintained at 70 to 90 °C. The polymerization conditions of the above examples are shown in Table 1 below.

[0116] [Table 1]

[0117] Comparative Example 1 For comparison, linear low density polyethylene VL0001 (density 0.900 g / cm 3 , melt index 1.0 g / 10 min) manufactured by DL Chemical Co., Ltd. and linear low density polyethylene M1810HA (density 0.9200 g / cm 3 , melt index 1.0 g / 10 min) manufactured by Hanwha Solux Co., Ltd. were used.

[0118] Test Example The physical properties of the olefin polymer of the above example were measured according to the following methods and criteria. The results are shown in Table 2 below.

[0119] (1) Density Measured according to ASTM D1505.

[0120] (2) Melt index and melt flow ratio (MFR) According to ASTM D1238, the melt index was measured at 190 °C under loads of 21.6 kg and 2.16 kg respectively, and the ratio (MI 21.6 / MI 2.16 ) was determined.

[0121] (3) Melting temperature and crystallization temperature The thermal properties of the resin were measured with a differential scanning calorimeter (DSC). A primary endothermic curve was obtained while heating from 30 °C to 170 °C at 10 °C / min. Then, after maintaining at 170 °C for 5 minutes, an exothermic curve was obtained while cooling from 170 °C to -20 °C at 10 °C / min. Then, a secondary endothermic curve was obtained while heating from -20 °C to 170 °C at 10 °C / min.

[0122]

Table 2

[0123] As can be confirmed from Table 2 and FIGS. 1 to 2 above, the olefin polymer according to the embodiment of the present invention has a high melting temperature and crystallization temperature and excellent heat resistance of the resin. Therefore, the olefin polymer according to the embodiment of the present invention can be used for spout pouches for high-temperature liquid containers and the like.

Industrial Applicability

[0124] The present invention can provide an olefin-based polymer having excellent heat resistance. Therefore, the olefin-based polymer according to an embodiment of the present invention can be used for a spout pouch for a high-temperature liquid container or the like.

Claims

1. The density is 0.9 to 0.95 g / cm ３ and is an olefin polymer that satisfies the following Mathematical Formulas 1a and 2a: The olefin polymer is a linear low-density polyethylene in which the olefin monomer is ethylene and the olefin comonomer is 1-hexene, The olefin polymer has a melt index (I ２．１６ ) of 0.5 to 3.0 g / 10 min as measured at 190°C under a load of 2.16 kg, and a melt index (I ２１．６ ) measured at 190°C under a load of 21.6 kg and a melt index (I ２．１６ ) measured under a load of 2.16 kg has a ratio (melt flow ratio; MFR) of 17 to 50, and a crystallization temperature (Tc) of 107.6 to 117°C, The olefin polymer is produced by polymerizing an olefin monomer in the presence of a hybrid catalyst containing at least one first transition metal compound represented by the following Chemical Formulas 1-1 and 1-2 and at least one second transition metal compound represented by the following Chemical Formulas 2-1, 2-2, and 3-1. An olefin polymer. [Formula 1a] 224.02 × d - 86.257 < Tm [Formula 2a] 219.64 × d - 95.767 < Tc In the above formula, Tm is the melting temperature (°C), Tc is the crystallization temperature (°C), and d is the density of the olefin polymer (g / cm ３ ). 【Chemical 1】

2. The olefin polymer according to Claim 1, which satisfies the following Formulas 1b and 2b. [Formula 1b] Tm < 224.02 × d - 82.257 [Formula 2b] Tc < 219.64 × d - 91.767 In the above formulas, Tm, Tc, and d are the same as described in Claim 1.

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