Ziegler-natta catalyst for olefin polymerization, method for preparing polyolefin, and polyolefin resin

Abstract

Provided are a Ziegler-Natta catalyst for olefin polymerization, a method for preparing polyolefin, and polyolefin resin. The Ziegler-Natta catalyst comprises: (i) a Ziegler-Natta pro-catalyst for olefin polymerization comprising a titanium compound represented by chemical formula 1, a magnesium compound represented by chemical formula 2, and an internal electron donor; (ii) an organic aluminum compound represented by chemical formula 7; and (iii) an external electron donor represented by chemical formula 3, wherein the internal electron donor comprises a mixture of a first internal electron donor represented by chemical formula 4, a second internal electron donor represented by chemical formula 5, and a third internal electron donor represented by chemical formula 6, the molar ratio of the external electron donor to the mixture being 115-130.

Description

Ziegler-Natta catalyst for olefin polymerization, method for producing polyolefin, and polyolefin resin

[0001] The present invention relates to a Ziegler-Natta catalyst for olefin polymerization, a method for producing a polyolefin with excellent processability using the same, and a polyolefin resin.

[0002]

[0003] Polyolefins are a class of polymers derived from simple olefins. Known methods for producing polyolefins involve the use of Ziegler-Natta polymerization catalysts. Ziegler-Natta polymerization catalysts use transition metal halides to polymerize vinyl monomers, producing polymers with a highly isotactic stereochemical configuration.

[0004] In particular, as polyethylene, one of the polyolefins, has recently been diversifying its applications, it may be desirable to manufacture polyethylene resin with excellent processability in order to improve resin productivity.

[0005] [Prior Art Literature]

[0006] [Patent Document]

[0007] Republic of Korea Patent Registration No. 10-2423660

[0008]

[0009] The purpose of the present invention is to provide a catalyst for producing a polyolefin having excellent processability by satisfying all of the density, melt index and melt flow ratio described in the present specification, and a method for producing a polyolefin having excellent processability.

[0010]

[0011] A Ziegler-Natta catalyst for olefin polymerization is provided.

[0012] According to one embodiment, a Ziegler-Natta catalyst for olefin polymerization comprises (i) a Ziegler-Natta pro-catalyst for olefin polymerization comprising a titanium compound represented by the following formula 1, a magnesium compound represented by the following formula 2, and an internal electron donor; (ii) an organoaluminum compound represented by the following formula 7; and (iii) an external electron donor represented by the following formula 3, wherein the internal electron donor comprises a mixture of a first internal electron donor represented by the following formula 4; a second internal electron donor represented by the following formula 5; and a third internal electron donor represented by the following formula 6, wherein a molar ratio of the external electron donor to the mixture is about 115 to about 130. In specific examples, the molar ratio of the external electron donor to the mixture may be about 117 to about 128, for example, about 117 to about 120, about 120 to 125, or about 125 to about 128.

[0013] [Chemical Formula 1]

[0014] TiX n (OR 1 ) 4-n

[0015] (In the above chemical formula 1,

[0016] R 1 C1-C substituted or unsubstituted 20 Alkyl group, substituted or unsubstituted C3-C 20 Cycloalkyl group, and substituted or unsubstituted C3-C 20 One selected from the group consisting of aryl groups,

[0017] X is a halogen atom,

[0018] n is an integer from 0 to 4, and

[0019] In the above substitution or non-substitution, the substituent is independently at least one selected from the group consisting of a halogen group, a cyano group, a nitro group, and a C1-C8 alkyl group.

[0020] [Chemical Formula 2]

[0021] Mg(OR 2 ) k X 2-k

[0022] (In the above chemical formula 2,

[0023] R 2 C1-C substituted or unsubstituted 20 Alkyl group, substituted or unsubstituted C3-C 20 Cycloalkyl group, and substituted or unsubstituted C3-C 20 One selected from the group consisting of aryl groups,

[0024] X is a halogen atom,

[0025] k is an integer from 0 to 2, and

[0026] In the above substitution or non-substitution, the substituent is independently at least one selected from the group consisting of a halogen group, a cyano group, a nitro group, and a C1-C8 alkyl group.

[0027] [Chemical Formula 3]

[0028]

[0029] (In the above chemical formula 3,

[0030] L1 and L2 are each independently substituted or unsubstituted C1-C 20 An alkyl group, and in the above substituted or unsubstituted, the substituent is independently at least one selected from the group consisting of a halogen group, a cyano group, a nitro group, and a C1-C8 alkyl group,

[0031] L3 and L4 are each independently substituted or unsubstituted C1-C 20 Alkyl group and substituted or unsubstituted C3-C 20 One species selected from the group consisting of cycloalkyl groups,

[0032] In the above substitution or non-substitution, the substituent is independently at least one selected from the group consisting of a halogen group, a cyano group, a nitro group, and a C1-C8 alkyl group.

[0033] [Chemical Formula 4]

[0034]

[0035] (In the above chemical formula 4,

[0036] R 3 C1-C substituted or unsubstituted 20 Alkyl group, substituted or unsubstituted C3-C 20 Cycloalkyl group, and substituted or unsubstituted C3-C 20 One selected from the group consisting of aryl groups, and in the above substituted or unsubstituted, the substituent is independently at least one selected from the group consisting of a halogen group, a cyano group, a nitro group, and a C1-C8 alkyl group,

[0037] R 4 and R 5 are each independently branched C1-C 20 alkyl group,

[0038] m is an integer from 0 to 4)

[0039] [Chemical Formula 5]

[0040]

[0041] (In the above chemical formula 5,

[0042] R 6 is independently, substituted or unsubstituted C1-C 20 Alkyl group, substituted or unsubstituted C3-C 20 Cycloalkyl group, and substituted or unsubstituted C3-C 20 One selected from the group consisting of aryl groups, and in the above substituted or unsubstituted, the substituent is independently at least one selected from the group consisting of a halogen group, a cyano group, a nitro group, and a C1-C8 alkyl group,

[0043] R 7 is a straight chain C1-C20 alkyl group,

[0044] R 8 C1-C of branched chain 20 alkyl group,

[0045] n is an integer from 0 to 4)

[0046] [Chemical Formula 6]

[0047]

[0048] (In the above chemical formula 6,

[0049] R 9 are each independently substituted or unsubstituted C1-C 20 Alkyl group, substituted or unsubstituted C3-C 20 Cycloalkyl group, and substituted or unsubstituted C3-C 20 One selected from the group consisting of aryl groups, and in the above substituted or unsubstituted, the substituent is independently at least one selected from the group consisting of a halogen group, a cyano group, a nitro group, and a C1-C8 alkyl group,

[0050] R 10 and R 11 are each independently straight-chain C1-C 20 alkyl group,

[0051] p is an integer from 0 to 4),

[0052] [Chemical Formula 7]

[0053] Al(R 13 ) p X 3-p

[0054] (In the above chemical formula 7,

[0055] R 13 Silver hydrogen atom, substituted or unsubstituted C1-C 20 Alkyl group, substituted or unsubstituted C3-C 20 Cycloalkyl group, and substituted or unsubstituted C3-C 20 One selected from the group consisting of aryl groups,

[0056] X is a halogen atom,

[0057] p is an integer from 0 to 3, and

[0058] In the above substitution or non-substitution, the substituent is independently at least one selected from the group consisting of a halogen group, a cyano group, a nitro group, and a C1-C8 alkyl group.

[0059] A method for producing polyolefin is provided.

[0060] According to one embodiment, a method for producing a polyolefin comprises the step of polymerizing an olefin monomer in the presence of a Ziegler-Natta catalyst for olefin polymerization:

[0061] A polyolefin resin is provided.

[0062] According to one embodiment, a melt flow ratio (MFR) is produced by the above manufacturing method. 21.6 / MFR 2.16 ) is about 20 to about 25. In a specific example, the melt flow ratio (MFR 21.6 / MFR 2.16 ) may be from about 20.2 to about 24.9, for example, from about 20.2 to about 21.5, from about 21.5 to about 22.5, from about 22.5 to about 23.5, from about 23.5 to about 24.8.

[0063]

[0064] By satisfying the density, melt index and melt flow ratio described in the present specification, the Ziegler-Natta catalyst for olefin polymerization produced a polyolefin with excellent processability.

[0065]

[0066] The above objectives, other objectives, features, and advantages will be readily understood through the following preferred embodiments, illustrated in the accompanying drawings. However, the embodiments described herein are not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided to ensure that the disclosed content is thorough and complete, and to sufficiently convey the technical concepts to those skilled in the art.

[0067] In describing each drawing, similar reference numerals are used to designate similar components. In the attached drawings, the dimensions of structures are shown exaggerated for clarity of the present invention. Terms such as first, second, etc. may be used to describe various components, but these components should not be limited by these terms. These terms are used only to distinguish one component from another. For example, without departing from the scope of the present invention, a first component could be referred to as a second component, and similarly, a second component could also be referred to as a first component.

[0068] Singular expressions include plural expressions unless the context clearly indicates otherwise.

[0069] In this specification, terms such as “include” or “have” are intended to specify the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but should be understood not to exclude in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0070] Unless otherwise specified, all numbers, values, and / or expressions expressing quantities of ingredients, reaction conditions, polymer compositions, and blends used herein are approximations that inherently reflect, among other things, the various uncertainties of measurement that arise in obtaining such values, and therefore should be understood as being modified in all instances by the term "about." Furthermore, whenever a numerical range is disclosed herein, such range is continuous and includes every value from the minimum value to the maximum value inclusive, unless otherwise indicated. Furthermore, whenever such a range refers to integers, every integer from the minimum value to the maximum value inclusive, unless otherwise indicated, is included.

[0071] In this specification, when a range is described for a variable, the variable will be understood to include all values ​​within the described range including the described endpoints of the range. For example, the range "5 to 10" will be understood to include the values ​​5, 6, 7, 8, 9, and 10, as well as any subranges such as 6 to 10, 7 to 10, 6 to 9, 7 to 9, etc., and any value between integers that fall within the described range, such as 5.5, 6.5, 7.5, 5.5 to 8.5, and 6.5 to 9. Also, for example, a range of "10% to 30%" would be understood to include all integers up to and including 30%, as well as any subranges such as 10% to 15%, 12% to 18%, 20% to 30%, etc., and any value between reasonable integers within the stated range, such as 10.5%, 15.5%, 25.5%, etc.

[0072] Recently, as polyethylene has been diversifying its uses, there has been a need for a catalyst and a method for producing polyethylene resin with excellent processability to improve resin productivity.

[0073] Accordingly, the inventors of the present invention have conducted extensive research to solve the above problem and have provided an olefin-Ziegler-Natta catalyst and a method for producing polyolefin, which allows for producing polyethylene with excellent processability by mixing three or more specific internal electron donors among main catalysts with a specific external electron donor and controlling the molar ratio between the external electron donor and the internal electron donor. Here, "excellent processability" may mean that the product is easy to manufacture by having an appropriate melt flow ratio.

[0074] Here, “polyethylene with excellent processability” can be a polyolefin that satisfies the following properties:

[0075] (i) Density: 0.950 to 0.965 g / cm 3

[0076] (ii) Melting index: 0.1 to 2.0 g / 10 min

[0077] (iii) Melt flow ratio: 20 to 25

[0078] The above density was measured by ASTM D1505.

[0079] The above melt index is the value at a load of 2.16 kg, and was measured at 190°C under a load of 2.16 kg according to ASTM D1238.

[0080] The above melt flow ratio (MFR) is the melt index (MI) at 2.16 kg at 190°C according to ASTM D1238. 2.16 ) and melt index (MI) at 21.6 kg at 190°C according to ASTM D1238 21.6 ) and measure the ratio MI between them 21.6 / MI 2.16 is the calculated value.

[0081] When the melt flow ratio is greater than 25, the processability of the polyolefin resin formed by polymerization is excellent, but the mechanical properties, such as tensile strength (breaking point), may be poor, resulting in poor final properties of the polymerized resin. When the melt flow ratio is less than 20, the processability of the polyolefin resin formed by polymerization may be poor. Preferably, the melt flow ratio may be about 21 to about 25. In specific examples, the melt flow ratio may be about 20.2 to about 24.9, for example, about 20.2 to about 21.5, about 21.5 to about 22.5, about 22.5 to about 23.5, or about 23.5 to about 24.8.

[0082] Unless otherwise stated, "C1-C n "Alkyl group" means a primary alkyl group having 1 to n carbon atoms, a secondary alkyl group (n ≥ 3), and a tertiary alkyl group (n ≥ 4). For example, it may be a functional group such as methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, tert-butyl, n-hexyl, etc.

[0083] Unless otherwise specified, “straight-chain” in the context of an alkyl group means that the carbon atom chain constituting the alkyl group is composed of a straight chain without any branches.

[0084] Unless otherwise specified, “branched” in the context of an alkyl group means that at least one portion of the carbon atom chain constituting the alkyl group has a branched chain.

[0085] Unless otherwise specified, an aryl group means a chemical group obtained by removing one hydrogen atom from a monocyclic or polycyclic compound having 2 to 30 carbon atoms and a derivative thereof containing one or more benzene rings, and examples of the monocyclic or polycyclic compound containing a benzene ring include a benzene ring, toluene or xylene having an alkyl side chain attached to a benzene ring, biphenyl having two or more benzene rings bonded by a single bond, fluorene, xanthene or anthraquinone having a benzene ring condensed with a cycloalkyl group or a heterocycloalkyl group, naphthalene or anthracene having two or more benzene rings condensed, and the like.

[0086] Unless otherwise specified, the prefix hetero means that one to three heteroatoms selected from the group consisting of -N-, -O-, -S- and -P- replace carbon atoms. For example, it can be pyridine, pyrrole or carbazole containing nitrogen as heteroatom, furan or dibenzofuran containing oxygen as heteroatom, or dibenzothiophene, diphenylamine etc.

[0087] Unless otherwise specified, halogen refers to a group 17 element, such as a fluoro, chloro, bromo or iodo group.

[0088] According to one embodiment, a Ziegler-Natta catalyst for olefin polymerization comprises (i) a main catalyst comprising a titanium compound described below, a magnesium compound described below, and an internal electron donor; (ii) an organoaluminum described below; and (iii) an external electron donor described below, wherein the main catalyst comprises a mixture of three types of internal electron donors described below, and the external electron donor and the mixture are included in a specific molar ratio.

[0089] Specifically, a Ziegler-Natta catalyst for olefin polymerization comprises a mixture of an external electron donor represented by the following chemical formula 3, wherein the internal electron donor comprises a first internal electron donor represented by the following chemical formula 4; a second internal electron donor represented by the following chemical formula 5; and a third internal electron donor represented by the following chemical formula 6, wherein a molar ratio of the external electron donor to the mixture is about 115 to about 130. In specific examples, the molar ratio of the external electron donor to the mixture may be about 117 to about 128, for example, about 117 to about 120, about 120 to 125, or about 125 to about 128. Here, the 'mole ratio' is (number of moles of external electron donor) / (number of moles of mixture).

[0090] [External electron donor]

[0091] External electron donors can play a role in stabilizing the catalytically active sites of titanium compounds among the main catalysts. The siloxane-based external electron donor represented by the following chemical formula 3 can facilitate the production of polyolefins with excellent processability when applied to the internal electron donor described below.

[0092] The external electron donor can be represented by the following chemical formula 3:

[0093] [Chemical Formula 3]

[0094]

[0095] (In the above chemical formula 3,

[0096] L1 and L2 are each independently substituted or unsubstituted C1-C 20 An alkyl group, and in the above substituted or unsubstituted, the substituent is independently at least one selected from the group consisting of a halogen group, a cyano group, a nitro group, and a C1-C8 alkyl group,

[0097] L3 and L4 are each independently substituted or unsubstituted C1-C 20 Alkyl group and substituted or unsubstituted C3-C20 One selected from the group consisting of cycloalkyl groups, and in the above substituted or unsubstituted, the substituent is independently at least one selected from the group consisting of a halogen group, a cyano group, a nitro group, and a C1-C8 alkyl group.

[0098] In one specific embodiment, at least one of L3 and L4 is a substituted or unsubstituted C3-C 20 It may be a cycloalkyl group. In this case, it may be easy to produce a polyolefin with excellent processability when applied to a mixture of internal electron donors described below.

[0099] For example, the external electron donor is a substituted or unsubstituted C3-C group among L3 and L4 in the above chemical formula 3. 20 Cycloalkyl group, for example, substituted or unsubstituted C3-C 10 The first external electron donor may be a cycloalkyl group, a substituted or unsubstituted C5-C6 cycloalkyl group.

[0100] For example, in the above formula 3, both L3 and L4 are substituted or unsubstituted C3-C 20 Cycloalkyl group, for example, substituted or unsubstituted C3-C 10 The second external electron donor may be a cycloalkyl group, a substituted or unsubstituted C5-C6 cycloalkyl group.

[0101] The external electron donor may include at least one of the first external electron donor and the second external electron donor.

[0102] Preferably, the external electron donor may be a second external electron donor. Since the second external electron donor binds more strongly to the crystal plane (110) of the magnesium compound than the first external electron donor, the number of final active sites is reduced, thereby reducing the melting index ratio, so that the melt flow ratio can easily reach about 20 to about 25. In a specific example, the melt flow ratio may be about 20.2 to about 24.9, for example, about 20.2 to about 21.5, about 21.5 to about 22.5, about 22.5 to about 23.5, or about 23.5 to about 24.8.

[0103] According to one embodiment, the catalyst may include one type of external electron donor represented by the chemical formula 3, i.e., the first external electron donor alone or the second external electron donor alone.

[0104] According to one embodiment, the catalyst may be a mixture comprising two types of external electron donors represented by the above chemical formula 3. In one specific embodiment, the catalyst may be a mixture of the first external electron donor and the second external electron donor. For example, in 10 moles of the mixture, the first external electron donor: the second external electron donor may be included in a molar ratio of 3:7 to 7:3, a molar ratio of 4:6 to 6:4, or a molar ratio of 5:5.

[0105] In one specific embodiment, L1 and L2 are each independently substituted or unsubstituted C1-C 10 An alkyl group, for example, a substituted or unsubstituted C1-C5 alkyl group.

[0106] In one specific example, the first external electron donor may be represented by the following chemical formula 3-1, and the second external electron donor may be represented by the following chemical formula 3-2:

[0107] [Chemical Formula 3-1]

[0108]

[0109] [Chemical Formula 3-2]

[0110]

[0111] According to one embodiment, the external electron donor may be included in an amount of about 30 wt% to about 50 wt% based on 100 wt% of the total Ziegler-Natta catalyst for olefin polymerization. Within this amount range, the stability of the catalyst active site may be high, and there may be no problem of activity reduction due to poisoning of the catalyst active site.

[0112] According to one embodiment, the external electron donor represented by the above chemical formula 3 may be included in an amount of about 95 wt% or more, preferably about 99 wt% to about 100 wt%, and more preferably about 100 wt%, based on 100 wt% of the total external electron donor contained in the Ziegler-Natta catalyst for olefin polymerization. Within this range, the effect of the present invention may be easily achieved. Here, the 'total external electron donor' may refer to a compound that is independently included compared to the main catalyst in the olefin Ziegler-Natta catalyst, and is known to those skilled in the art to play a role in stabilizing the catalytic active site of the titanium compound.

[0113] [Internal electron donor]

[0114] The internal electron donor is selected so that, when the external electron donor is included in the olefin-Ziegler-Natta catalyst, the polyolefin with excellent processability, i.e., satisfies a specific range of density, melt index, and melt index ratio. The internal electron donor provides various active sites when the external electron donor is applied, thereby enabling the production of a polyolefin resin with excellent processability.

[0115] In the present invention, the external electron donor comprises a mixture of a first internal electron donor represented by the following chemical formula 4; a second internal electron donor represented by the following chemical formula 5; and a third internal electron donor represented by the following chemical formula 6, wherein the molar ratio of the external electron donor to the mixture is about 115 to about 130. In a specific example, the molar ratio of the external electron donor to the mixture may be about 117 to about 128, for example, about 117 to about 120, about 120 to 125, or about 125 to about 128:

[0116] [Chemical Formula 4]

[0117]

[0118] (In the above chemical formula 4,

[0119] R 3 C1-C substituted or unsubstituted 20 Alkyl group, substituted or unsubstituted C3-C 20 Cycloalkyl group, and substituted or unsubstituted C3-C 20 One selected from the group consisting of aryl groups, and in the above substituted or unsubstituted, the substituent is independently at least one selected from the group consisting of a halogen group, a cyano group, a nitro group, and a C1-C8 alkyl group,

[0120] R 4 and R 5 is independently, branched-chain C1-C 20 alkyl group,

[0121] m is an integer from 0 to 4)

[0122] [Chemical Formula 5]

[0123]

[0124] (In the above chemical formula 5,

[0125] R 6 is independently, substituted or unsubstituted C1-C 20 Alkyl group, substituted or unsubstituted C3-C 20Cycloalkyl group, and substituted or unsubstituted C3-C 20 One selected from the group consisting of aryl groups, and in the above substituted or unsubstituted, the substituent is independently at least one selected from the group consisting of a halogen group, a cyano group, a nitro group, and a C1-C8 alkyl group,

[0126] R 7 is a straight chain C1-C 20 alkyl group,

[0127] R 8 C1-C of branched chain 20 alkyl group,

[0128] n is an integer from 0 to 4)

[0129] [Chemical Formula 6]

[0130]

[0131] (In the above chemical formula 6,

[0132] R 9 are each independently substituted or unsubstituted C1-C 20 Alkyl group, substituted or unsubstituted C3-C 20 Cycloalkyl group, and substituted or unsubstituted C3-C 20 One selected from the group consisting of aryl groups, and in the above substituted or unsubstituted, the substituent is independently at least one selected from the group consisting of a halogen group, a cyano group, a nitro group, and a C1-C8 alkyl group,

[0133] R 10 and R 11 are each independently straight-chain C1-C 20 alkyl group,

[0134] p is an integer from 0 to 4).

[0135] The mixture comprises a first internal electron donor, a second internal electron donor and a third internal electron donor.

[0136] With respect to the above external electron donor, the olefin-Ziegler-Natta catalyst containing only the first internal electron donor, only the second internal electron donor, or only the third internal electron donor may have difficulty in producing a polyolefin that satisfies all of the above-described density, melt index, and melt flow ratio, and in particular, may have difficulty in satisfying the above-described melt flow ratio, resulting in poor processability. With respect to the above external electron donor, the olefin-Ziegler-Natta catalyst containing only two of the first internal electron donor, the second internal electron donor, and the third internal electron donor may have difficulty in producing a polyolefin that satisfies all of the above-described density, melt index, and melt flow ratio, and in particular, may have difficulty in satisfying the above-described melt flow ratio, resulting in poor processability. Even if the olefin-Ziegler-Natta catalyst includes a mixture of the internal electron donor and the external electron donor, the molar ratio of the external electron donor to the mixture is less than 115 or greater than 130, making it difficult to produce a polyolefin that satisfies all of the above-described density, melt index, and melt flow ratio, and in particular, it may be difficult to satisfy the above-described melt flow ratio, resulting in poor processability.

[0137] In one specific example, the molar ratio of the external electron donor to the mixture may be 115 to 125.

[0138] In one specific embodiment, the mixture may include one or more first internal electron donors.

[0139] In one specific embodiment, the mixture may include one or more second internal electron donors.

[0140] In one specific example, the mixture may include two or more third internal electron donors.

[0141] In one specific example, the mixture may be included in a weight ratio of the first internal electron donor > the third internal electron donor > the second internal electron donor. Within this range, the present invention's effect may be easily realized.

[0142] For example, the first internal electron donor may be included in the mixture in an amount of about 50 to about 80 wt%, preferably about 60 to about 80 wt%, the second internal electron donor may be included in the mixture in an amount of about 1 to about 20 wt%, preferably about 5 to about 15 wt%, and the third internal electron donor may be included in the mixture in an amount of about 10 to about 40 wt%, preferably about 15 to about 35 wt%. Within these ranges, the effects of the present invention may be easily achieved.

[0143] In one specific embodiment, the mixture of internal electron donors may be included in the olefin Ziegler-Natta catalyst in an amount of about 10 to about 20 wt%, for example, about 10 to about 15 wt%. Within this range, the present invention's effects may be readily achieved.

[0144] In one specific example, in the chemical formula 4, R 4 and R 5 is independently, branched-chain C3-C 10 An alkyl group, a C3-C5 alkyl group. For example, in the above chemical formula 4, R 4 and R 5 is independently branched C3-C 10 It may be an alkyl group, a C3-C5 alkyl group. The first internal electron donor represented by the above chemical formula 4 may include at least one compound represented by any one of the chemical formulas 4-1 to 4-3 below:

[0145] [Chemical Formula 4-1]

[0146]

[0147] [Chemical Formula 4-2]

[0148]

[0149] [Chemical Formula 4-3]

[0150]

[0151] In one specific example, in the chemical formula 5, R7 is a straight chain C1-C 10 It may be an alkyl group, or a straight-chain C1-C5 alkyl group. In the above chemical formula 5, R 8 C2-C of branched chain 10 It may be an alkyl group, a C2-C5 alkyl group. For example, in the above chemical formula 5, R 8 C2-C, branched at the terminal end 10 It may be an alkyl group, a C2-C5 alkyl group. For example, the second internal electron donor represented by the above chemical formula 5 may include at least one compound represented by any one of the chemical formulas 5-1 to 5-4 below:

[0152] [Chemical Formula 5-1]

[0153]

[0154] [Chemical Formula 5-2]

[0155]

[0156] [Chemical Formula 5-3]

[0157]

[0158] [Chemical Formula 5-4]

[0159]

[0160] In one specific example, in the chemical formula 6, R 10 and R 11 are each independently straight-chain C1-C 10 An alkyl group may be a straight-chain C1-C5 alkyl group. For example, the third internal electron donor represented by the above chemical formula 6 may include at least one compound represented by any one of the chemical formulas 6-1 to 6-3 below:

[0161] [Chemical Formula 6-1]

[0162]

[0163] [Chemical Formula 6-2]

[0164]

[0165] [Chemical Formula 6-3]

[0166]

[0167] According to one embodiment, the mixture of the first internal electron donor, the second internal electron donor, and the third internal electron donor may be included in an amount of about 95 wt% or more, preferably about 99 wt% to about 100 wt%, and more preferably about 100 wt%, based on 100 wt% of the total internal electron donors contained in the Ziegler-Natta catalyst for olefin polymerization. In this range, the effects of the present invention may be easily achieved. Here, the 'total internal electron donor' may mean a compound included in the main catalyst of the olefin Ziegler-Natta catalyst, and a compound known to those skilled in the art to play a role in stabilizing the catalytic active site of a titanium compound.

[0168] [Titanium compounds]

[0169] The titanium compound may be a compound containing an active center metal, i.e., a metal having an active site. The titanium compound can provide a polyolefin by catalyzing the actual polymerization reaction of an olefinic monomer.

[0170] Titanium compounds are compounds represented by the chemical formula 1 below.

[0171] [Chemical Formula 1]

[0172] TiX n (OR 1 ) 4-n

[0173] (In the above chemical formula 1,

[0174] R 1 C1-C substituted or unsubstituted 20 Alkyl group, substituted or unsubstituted C3-C 20 Cycloalkyl group, and substituted or unsubstituted C3-C 20 One selected from the group consisting of aryl groups,

[0175] X is a halogen atom,

[0176] n is an integer from 0 to 4, and

[0177] In the above substitution or non-substitution, the substituent is independently at least one selected from the group consisting of a halogen group, a cyano group, a nitro group, and a C1-C8 alkyl group.

[0178] For example, the titanium compound may be at least one selected from the group consisting of tetravalent titanium halides and tetravalent titanium alkoxides. Preferably, the titanium compound may be titanium tetrachloride (TiCl4), titanium trichloride ethoxide (Ti(OC2H5)Cl3), or the like.

[0179] [magnesium compounds]

[0180] Magnesium compounds can control the properties, such as the activity and stereoregularity of the active center metal having an active site, such as a titanium compound, depending on the molecular structure and bonding strength through bonding with an electron donor as a catalyst support.

[0181] Magnesium compounds are compounds represented by the following chemical formula 2:

[0182] [Chemical Formula 2]

[0183] Mg(OR 2 ) k X 2-k

[0184] (In the above chemical formula 2,

[0185] R 2 C1-C substituted or unsubstituted 20 Alkyl group, substituted or unsubstituted C3-C 20 Cycloalkyl group, and substituted or unsubstituted C3-C 20 One selected from the group consisting of aryl groups,

[0186] X is a halogen atom,

[0187] k is an integer from 0 to 2, and

[0188] In the above substitution or non-substitution, the substituent is independently at least one selected from the group consisting of a halogen group, a cyano group, a nitro group, and a C1-C8 alkyl group.

[0189] For example, the magnesium compound may be magnesium dialkoxide, magnesium diaryloxide, or magnesium chloride (MgCl2), and preferably, magnesium diethoxide, which has the advantage of having high purity as magnesium dialkoxide, thereby reducing impurities in the final synthesized catalyst, and being well soluble in a solvent during catalyst synthesis.

[0190] [organic aluminum compounds]

[0191] Organoaluminum compounds can act as cocatalysts to activate the active sites of titanium compounds.

[0192] The organoaluminum compound may include a compound of formula 7 below:

[0193] [Chemical Formula 7]

[0194] Al(R 13 ) p X 3-p

[0195] (In the above chemical formula 7,

[0196] R 13 Silver hydrogen atom, substituted or unsubstituted C1-C 20 Alkyl group, substituted or unsubstituted C3-C 20 Cycloalkyl group, and substituted or unsubstituted C3-C 20 One selected from the group consisting of aryl groups,

[0197] X is a halogen atom,

[0198] p is an integer from 0 to 3, and

[0199] In the above substitution or non-substitution, the substituent is independently at least one selected from the group consisting of a halogen group, a cyano group, a nitro group, and a C1-C8 alkyl group.

[0200] According to one embodiment, the organoaluminum compound may be at least one selected from the group consisting of trimethylaluminum, triethylaluminum, triisobutylaluminum, trioctylaluminum, diethylaluminum hydride, diisobutylaluminum hydride, diethylaluminum chloride, diisobutylaluminum chloride, sesquiethylaluminum chloride, and ethylaluminum dichloride. Preferably, the organoaluminum compound may be triethylaluminum, which can increase polymerization activity and facilitate control of the weight average molecular weight of the polymerized polyolefin.

[0201] [Main catalyst]

[0202] The main catalyst comprises a titanium compound represented by the above chemical formula 1, a magnesium compound represented by the above chemical formula 2, and the internal electron donor, wherein the titanium compound represented by the above chemical formula 1 and the internal electron donor may be supported on a magnesium compound represented by the above chemical formula 2.

[0203] According to one embodiment, the main catalyst may be in a powder state. As described below, a Ziegler-Natta catalyst for olefin polymerization according to one embodiment may be prepared by mixing an organoaluminum compound and an external electron donor with the main catalyst.

[0204] The main catalyst in powder form can be uniformly coated with an organoaluminum compound and an external electron donor. This facilitates the production of a polyolefin having the aforementioned density, melt index, and melt index ratio by ensuring that the main catalyst in powder form is well dispersed within the organoaluminum compound and the external electron donor, thereby enhancing dispersion stability.

[0205] A method for producing a Ziegler-Natta primary catalyst for olefin polymerization may include a first step of mixing a titanium compound represented by Chemical Formula 1 and a magnesium compound represented by Chemical Formula 2 and stirring them; a second step of adding a mixture of internal electron donors to the first stirring resultant and stirring them; and a step of vacuum-drying the second stirring resultant.

[0206] The above first stirring step is a step of adding a titanium compound and a magnesium compound to an organic solvent and then stirring at a heating rate of about 0.5°C / min to about 1.5°C / min from room temperature to the first temperature.

[0207] The organic solvent may be toluene, ether, acetone, alcohol, etc., and preferably, toluene.

[0208] The first temperature may be a temperature of about 70°C to about 90°C, and preferably, a temperature of about 75°C to about 85°C. In specific examples, the first temperature may be about 72°C to about 88°C, for example, about 72°C to about 75°C, about 75°C to about 80°C, about 80°C to about 85°C, or about 85°C to about 88°C. Outside the first temperature range, if the first temperature is too low, there is a disadvantage that the internal electron donor does not dissolve in the solvent, and if the first temperature is too high, there is a disadvantage that a side reaction of the internal electron donor occurs.

[0209] The second stirring step is a step of adding an internal electron donor to the first stirring result, then raising the temperature to a second temperature, and stirring for about 1.8 hours to about 2.2 hours. In specific examples, the stirring time may be about 1.82 hours to about 1.9 hours, about 1.9 hours to about 2 hours, or about 2 hours to about 2.2 hours.

[0210] The second temperature may be about 100°C to about 120°C, and preferably, about 105°C to about 115°C. In specific examples, the second temperature may be about 102°C to about 118°C, for example, about 102°C to about 110°C, or about 110°C to about 118°C. Outside the second temperature range, if the second temperature is too low, there is a disadvantage that the titanium compound is not supported on the magnesium compound, and if the second temperature is too high, there is a disadvantage that the solvent evaporates.

[0211] After the second stirring, a third stirring step may be additionally included. Specifically, this is a step of removing the organic solvent and the titanium compound, adding a new organic solvent and the titanium compound, then increasing the temperature from room temperature to the third temperature, and stirring for about 1.8 hours to about 2.2 hours. In specific examples, this may be about 1.82 hours to about 1.9 hours, about 1.9 hours to about 2 hours, or about 2 hours to about 2.2 hours. After stirring, a step of washing the third stirring result using an organic solvent or the like may be further included.

[0212] The third temperature may be about 100°C to about 120°C, and preferably, about 105°C to about 115°C. In specific embodiments, the third temperature may be about 102°C to about 118°C, for example, about 102°C to about 110°C, about 110°C to about 118°C.

[0213] The vacuum drying step is a step of drying the second stirring result or the third stirring result in a vacuum to obtain a Ziegler-Natta main catalyst for olefin polymerization in powder form. At this time, a step of washing the second stirring result or the third stirring result with an organic solvent or the like may be further included before vacuum drying.

[0214] Ziegler-Natta catalyst for olefin polymerization

[0215] The titanium compound and the external electron donor of the Ziegler-Natta primary catalyst for olefin polymerization may be included in a molar ratio of about 1:3 to about 1:9, preferably, a molar ratio of about 1:4 to about 1:8. In a specific example, the titanium compound and the external electron donor of the Ziegler-Natta primary catalyst for olefin polymerization may be included in a molar ratio of about 1:3.2 to about 1:8.8, for example, about 1:3.2 to about 1:5, about 1:5 to about 1:7, or about 1:7 to about 1:8.8. In the above molar ratio range, the stability of the catalyst active site is excellent, and there may be no problem of the catalyst activity being reduced due to poisoning of the catalyst active site.

[0216] The organoaluminum compound and the external electron donor of the Ziegler-Natta main catalyst for olefin polymerization may be included in a molar ratio of about 1:0.01 to about 1:0.08, preferably, about 1:0.02 to about 1:0.06. In a specific example, the organoaluminum compound and the external electron donor of the Ziegler-Natta main catalyst for olefin polymerization may be included in a molar ratio of about 1:0.02 to about 1:0.07, for example, about 1:0.02 to about 1:0.04, about 1:0.04 to about 1:0.06, or about 1:0.06 to about 1:0.07. In the above molar ratio range, it may be easy to produce a polyolefin with excellent processability.

[0217] The magnesium compound and the external electron donor of the Ziegler-Natta primary catalyst for olefin polymerization may be included in a molar ratio of about 1:4 to about 1:12, preferably, about 1:6 to about 1:9. In a specific example, the magnesium compound and the external electron donor of the Ziegler-Natta primary catalyst for olefin polymerization may be included in a molar ratio of about 1:5 to about 1:11, for example, about 1:5 to about 1:7, about 1:7 to about 1:9, or about 1:9 to about 1:11. In the above molar ratio range, it may be easy to produce a polyolefin with excellent processability.

[0218] A method for preparing a Ziegler-Natta catalyst for olefin polymerization includes a step of adding a Ziegler-Natta main catalyst for olefin polymerization, an organoaluminum compound represented by chemical formula 7, and an external electron donor represented by chemical formula 3 to an organic solvent and then stirring the mixture. In this case, among the contents related to the method for preparing a Ziegler-Natta catalyst for olefin polymerization, any contents that overlap with the Ziegler-Natta catalyst for olefin polymerization may be omitted for explanation.

[0219] The organic solvent may be hexane, toluene, ether, acetone, alcohol, etc., and preferably, hexane.

[0220] The stirring speed may be about 280 rpm to about 320 rpm, and preferably, about 290 rpm to about 310 rpm. In specific examples, the stirring speed may be about 285 rpm to about 315 rpm, for example, about 285 rpm to about 295 rpm, about 295 rpm to about 305 rpm, or about 305 rpm to about 315 rpm.

[0221] [Polyolefin manufacturing method]

[0222] According to one embodiment, a method for producing a polyolefin comprises a step of polymerizing an olefin monomer in the presence of a Ziegler-Natta catalyst for olefin polymerization.

[0223] According to one embodiment, the olefinic monomer may include an olefinic monomer having the following chemical formula 8:

[0224] [Chemical Formula 8]

[0225] CH2=CHR 14

[0226] (In the above chemical formula 8,

[0227] R 14 is hydrogen or C1-C6 alkyl or aryl group)

[0228] In one embodiment, the method for producing polyolefin may be a method for producing polyethylene. Accordingly, the method may include a step of introducing and polymerizing an olefin monomer, preferably ethylene, in the presence of a Ziegler-Natta catalyst for olefin polymerization.

[0229] The polyolefin manufacturing method can be polymerized under conditions of a pressure of about 6 bar to about 8 bar and a temperature of about 80°C to about 90°C in a hydrogen gas atmosphere. In addition, if the temperature is too low, the catalyst may not be active, which may result in polymerization failure. If the temperature is too high, the catalyst may overreact, which may result in rapid decrease in activity.

[0230] The polymerization time may be from about 0.5 hours to about 1.5 hours, preferably from about 0.8 hours to about 1.2 hours.

[0231] According to one embodiment, the Ziegler-Natta catalyst for olefin polymerization is about 1 x 10 for 1 mole of olefin monomer. -5 About 3 x 10 -5 moles, preferably about 1.5 x 10 -5 About 2.5 x 10 -5 It can be included in moles. In a specific example, for 1 mole of the olefin monomer, the Ziegler-Natta catalyst for olefin polymerization is about 1.2 x 10 -5 About 2.9 x 10 -5 moles, for example, about 1.2 x 10 -5 About 1.5 x 10 -5 , about 1.5 x 10 -5 About 2 x 10 -5 , About 2 x 10 -5 About 2.5 x 10 -5 , about 2.5 x 10 -5 About 2.9 x 10 -5 It could be. In the above range, the polymerization yield of polyolefin from olefin monomer can be high.

[0232] [Polyolefin resin]

[0233] According to one embodiment, a polyolefin resin is provided. The polyolefin resin is manufactured by the above manufacturing method and has an MFR ratio (MFI) 21.6 / MFI 2.16 ) is about 20 to about 25. In a specific example, the MFR ratio (MFR 21.6 / MFR 2.16 ) may be from about 20.2 to about 24.9, for example, from about 20.2 to about 21.5, from about 21.5 to about 22.5, from about 22.5 to about 23.5, from about 23.5 to about 24.8.

[0234]

[0235] The present invention will be described in more detail below through examples. However, these examples are intended to exemplify the present invention and the scope of the present invention is not limited to these examples.

[0236]

[0237] The specific specifications of the components used in the examples and comparative examples below are as follows:

[0238] External electron donor:

[0239] [Chemical Formula 3-1]

[0240]

[0241] [Chemical Formula 3-2]

[0242]

[0243] Internal electron donor:

[0244] [Chemical Formula 4-1]

[0245]

[0246] [Chemical Formula 5-1]

[0247]

[0248] [Chemical Formula 6-1]

[0249]

[0250] [Chemical Formula 6-2]

[0251]

[0252] [Chemical Formula 6-3]

[0253]

[0254]

[0255] Example 1

[0256] Preparation of Ziegler-Natta primary catalysts for olefin polymerization

[0257] Add 4g of magnesium compound Mg(OC2H5)2 carrier and 8ml of titanium compound TiCl4 to 12ml of toluene and stir at room temperature for 80 o 1 to C o The temperature was increased at a rate of C / min and the first stirring was performed. Then, the reaction temperature was 80 o When C is reached, a mixture of internal electron donors is added to the first stirred result and 110 o 1 to C o After heating at a heating rate of C / min, the mixture was stirred for 2 hours while maintaining the temperature. Then, the TiCl4+Toluene solution was removed, and new TiCl4 (10 ml)+toluene (30 ml) was added, and the mixture was stirred at room temperature for 110 o 1 to C o The temperature was increased at a rate of C / min and maintained while stirring for a third time for 2 hours. Then, the supported catalyst, which was the result of the third stirring, was washed twice with 50 ml of toluene at 100°C and twice with 100 ml of hexane at 60°C, and dried in a vacuum to obtain a Ziegler-Natta main catalyst (supported catalyst) for olefin polymerization in powder form.

[0258] The mixture of the above internal electron donors is a mixture of chemical formula 4-1 (4.5 mmol), chemical formula 5-1 (0.45 mmol), chemical formula 6-1 (0.45 mmol), chemical formula 6-2 (0.45 mmol), and chemical formula 6-3 (0.45 mmol).

[0259]

[0260] Ziegler-Natta catalysts for olefin polymerization and polyethylene production

[0261] A 2-liter high-pressure reactor was dried in an oven, assembled while hot, and then a nitrogen atmosphere was created inside the reactor by alternately operating nitrogen and vacuum three times. Then, 1000 ml of hexane, an organic solvent, was added to the reactor, and 15 mg of a Ziegler-Natta main catalyst for olefin polymerization (Preparation Example 1), 0.18 ml of an external electron donor of chemical formula 3-2, and 2 mmol of triethylaluminum (2 ml of a 1 M hexane solution) as an organoaluminum compound (cocatalyst) were additionally added, and stirred at 300 rpm to prepare a Ziegler-Natta catalyst for olefin polymerization.

[0262] Next, the temperature of the reactor was raised to 85°C, 3 bar of hydrogen was injected once, and then polyethylene polymerization was performed for one hour while continuously adding ethylene at a constant pressure of 7 bar. Next, the temperature of the reactor was lowered to room temperature, and the produced polymer was separated, collected, and dried to obtain a white powdery polyethylene resin.

[0263]

[0264] Examples 2 to 5

[0265] In Example 1, a Ziegler-Natta main catalyst for olefin polymerization and a Ziegler-Natta catalyst for olefin polymerization were prepared and a polyethylene resin was prepared in the same manner as in Example 1, except that the internal electron donor and the external electron donor were changed as shown in Tables 1 and 2 below and the contents of each of the internal electron donor and the external electron donor were changed.

[0266]

[0267] Comparative Examples 1 to 17

[0268] In Example 1, a Ziegler-Natta main catalyst for olefin polymerization and a Ziegler-Natta catalyst for olefin polymerization were prepared and a polyethylene resin was prepared in the same manner as in Example 1, except that the internal electron donor and the external electron donor were changed as shown in Tables 1 and 2 below and the contents of each of the internal electron donor and the external electron donor were changed.

[0269]

[0270] Polyethylene property evaluation method

[0271] 1)Activity (G) PE / G cat ) (Unit: None): Calculated as the weight of polyethylene obtained (g) / weight of catalyst used (g).

[0272] 2)MFI 2.16 (Unit: g / 10min) and MFI 21.6 (Unit: g / 10min): Melt index measuring device was used for the obtained polyethylene, and according to ASTM D 1238, the load (MFI) of 2.16 kg at 190℃ 2.16 ) and a load of 21.6 kg (MFI 21.6 ) was measured.

[0273] 3) Melt flow ratio: melt index MFI 21.6 and MFI 2.16 2) are measured according to ASTM D 1238 and the ratio is MFR = (MFI) 21.6 / MFI 2.16 ) was saved.

[0274] 4) Density (unit: g / cm) 3 ): Measured according to ASTM D1505.

[0275] 5) Tensile strength (breaking point, unit: kgf / cm) 2): Measured using a tensile tester. Measured in each of the MD (machine direction) and TD (transverse direction) directions for polyethylene.

[0276]

[0277] Catalyst Ti (wt%) Chemical Formula 6-1 (wt%) Chemical Formula 6-2 (wt%) Chemical Formula 5-1 (wt%) Chemical Formula 6-3 (wt%) Chemical Formula 4-1 (wt%) Total Internal Electron Donor (wt%) Manufacturing Example 12.41.00.81.20.98.212.1 Manufacturing Example 22.41.0-1.11.28.111.4 Manufacturing Example 32.61.2-0.9-8.911.0 Manufacturing Example 42.7----9.49.4 Manufacturing Example 52.41.50.81.20.98.212.6 Manufacturing Example 62.41.00.41.20.98.211.7 Manufacturing Example 72.41.01.21.20. 98.212.5 Manufacturing Example 82.41.00.80.70.98.211.6 Manufacturing Example 92.41.00.81.70.98.212.6 Manufacturing Example 102.41.00.81.20.48.212.6 Manufacturing Example 112.41.00.81.21.48.211.6 Manufacturing Example 122.41.00.81.20.97.213.1 Manufacturing Example 132.41.00.81.20.99.211.1

[0278] *In Table 1 above, 'wt%' is the weight% of the content of each component in the Ziegler-Natta catalyst for olefin polymerization.

[0279]

[0280] CatalystExternal electron donorExternal electron donor / Internal electron donor (mol / mol)Example 1Preparation example 1Chemical formula 3-2115Example 2Preparation example 2Chemical formula 3-2123Example 3Preparation example 1Chemical formula 3-2130Example 4Preparation example 2Chemical formula 3-2115Example 5Preparation example 2Chemical formula 3-2129Comparative example 1Preparation example 1Chemical formula 3-1133Comparative example 2Preparation example 2Chemical formula 3-1144Comparative example 3Preparation example 3Chemical formula 3-2133Comparative example 4Preparation example 3Chemical formula 3-1155Comparative example 5Preparation example 4Chemical formula 3-2175Comparative example 6Preparation example 4Chemical formula 3-1205Comparative example 7Preparation example 5Chemical formula 3-2109Comparative example 8Preparation example 6Chemical formula 3-2113 Comparative Example 9 Manufacturing Example 7 Chemical Formula 3-2105 Comparative Example 10 Manufacturing Example 8 Chemical Formula 3-2110 Comparative Example 11 Manufacturing Example 9 Chemical Formula 3-2101 Comparative Example 12 Manufacturing Example 10 Chemical Formula 3-2105 Comparative Example 13 Manufacturing Example 11 Chemical Formula 3-298 Comparative Example 14 Manufacturing Example 12 Chemical Formula 3-2105 Comparative Example 15 Manufacturing Example 13 Chemical Formula 3-292 Comparative Example 16 Manufacturing Example 1 Chemical Formula 3-2230 Comparative Example 17 Manufacturing Example 1 Chemical Formula 3-258

[0281] *In Table 2 above, ‘external electron donor / internal electron donor’ is the molar ratio of the external electron donor to the mixture of internal electron donors among the Ziegler-Natta catalysts for olefin polymerization.

[0282]

[0283] Discriminative activity MFI (I 2.16 )MFI (I 21.6 )MFR (I 2.16 / I 21.6) Density Tensile strength (breaking point, MD / TD) Example 14, 6211.021.621.60.956390 / 360 Example 24, 4641.123.521.40.955380 / 360 Example 34, 6510.922.024.40.954370 / 350 Example 44, 5211.224.220.20.954390 / 360 Example 54, 7950.819.123.90.955360 / 340 Comparative Example 14, 2541.12 9.827.10.958350 / 330Comparative Example 24,1891.026.526.50.957355 / 335Comparative Example 34,0590.916.017.80.958410 / 380Comparative Example 43,9611.223.519.60.957400 / 370Comparative Example 53,9241.141.016.10.956440 / 410Comparative Example 63,8651.018.018.00.957420 / 390B 73.7561.025.625.60.955380 / 350Comparative Example 83,7560.916.718.60.956410 / 375Comparative Example 93,7451.026.526.50.954375 / 345Comparative Example 103,8361.121.019.10.955400 / 370Comparative Example 113,7561.128.525.90.956360 / 340Comparative Example 123,6991.018.41 8.40.955410 / 375Comparative Example 133,5460.923.826.40.957375 / 345Comparative Example 143,7841.017.517.50.956430 / 405Comparative Example 153,5460.925.328.10.955350 / 325Comparative Example 163,9541.016.516.50.955440 / 410Comparative Example 174,1211.131.428.50.956340 / 320

[0284]

[0285] Referring to Table 3 above, the Ziegler-Natta catalyst for olefin polymerization of the example produced a polyolefin that simultaneously satisfies the original density, melt index, and melt flow ratio.

[0286] On the other hand, the Ziegler-Natta catalyst for olefin polymerization that does not satisfy the original composition could not produce a polyolefin that simultaneously satisfies the original density, melt index, and melt flow ratio.

[0287]

[0288] Simple modifications or changes of the present invention can be easily implemented by a person having ordinary skill in the art, and all such modifications or changes can be considered to be included in the scope of the present invention.

[0289]

[0290] By satisfying the density, melt index and melt flow ratio described in the present specification, the Ziegler-Natta catalyst for olefin polymerization produced a polyolefin with excellent processability.

Claims

1. (i) A Ziegler-Natta pro-catalyst for olefin polymerization comprising a titanium compound represented by the following chemical formula 1, a magnesium compound represented by the following chemical formula 2, and an internal electron donor; (ii) an organoaluminum compound represented by the following chemical formula 7; and (iii) Contains an external electron donor represented by the following chemical formula 3, The internal electron donor comprises a mixture of a first internal electron donor represented by the following chemical formula 4; a second internal electron donor represented by the following chemical formula 5; and a third internal electron donor represented by the following chemical formula 6. A Ziegler-Natta catalyst for olefin polymerization, wherein the molar ratio of the external electron donor to the above mixture is 115 to 130: [Chemical Formula 1] TiX n (OR 1 ) 4-n (In the above chemical formula 1, R 1 C1-C substituted or unsubstituted 20 Alkyl group, substituted or unsubstituted C3-C 20 Cycloalkyl group, and substituted or unsubstituted C3-C 20 One selected from the group consisting of aryl groups, X is a halogen atom, n is an integer from 0 to 4, and In the above substitution or non-substitution, the substituent is independently at least one selected from the group consisting of a halogen group, a cyano group, a nitro group, and a C1-C8 alkyl group. [Chemical Formula 2] Mg(OR 2 ) k X 2-k (In the above chemical formula 2, R 2 C1-C substituted or unsubstituted 20 Alkyl group, substituted or unsubstituted C3-C 20 Cycloalkyl group, and substituted or unsubstituted C3-C 20 One selected from the group consisting of aryl groups, X is a halogen atom, k is an integer from 0 to 2, and In the above substitution or non-substitution, the substituent is independently at least one selected from the group consisting of a halogen group, a cyano group, a nitro group, and a C1-C8 alkyl group. [Chemical Formula 3] (In the above chemical formula 3, L1 and L2 are each independently substituted or unsubstituted C1-C 20 An alkyl group, and in the above substituted or unsubstituted, the substituent is independently at least one selected from the group consisting of a halogen group, a cyano group, a nitro group, and a C1-C8 alkyl group, L3 and L4 are each independently substituted or unsubstituted C1-C 20 Alkyl group and substituted or unsubstituted C3-C 20 One species selected from the group consisting of cycloalkyl groups, In the above substitution or non-substitution, the substituent is independently at least one selected from the group consisting of a halogen group, a cyano group, a nitro group, and a C1-C8 alkyl group. [Chemical Formula 4] (In the above chemical formula 4, R 3 C1-C substituted or unsubstituted 20 Alkyl group, substituted or unsubstituted C3-C 20 Cycloalkyl group, and substituted or unsubstituted C3-C 20 One selected from the group consisting of aryl groups, and in the above substituted or unsubstituted, the substituent is independently at least one selected from the group consisting of a halogen group, a cyano group, a nitro group, and a C1-C8 alkyl group, R 4 and R 5 are each independently branched C1-C 20 alkyl group, m is an integer from 0 to 4) [Chemical Formula 5] (In the above chemical formula 5, R 6 is independently, substituted or unsubstituted C1-C 20 Alkyl group, substituted or unsubstituted C3-C 20 Cycloalkyl group, and substituted or unsubstituted C3-C 20 One selected from the group consisting of aryl groups, and in the above substituted or unsubstituted, the substituent is independently at least one selected from the group consisting of a halogen group, a cyano group, a nitro group, and a C1-C8 alkyl group, R 7 is a straight chain C1-C 20 alkyl group, R 8 C1-C of branched chain 20 alkyl group, n is an integer from 0 to 4) [Chemical Formula 6] (In the above chemical formula 6, R 9 are each independently substituted or unsubstituted C1-C 20 Alkyl group, substituted or unsubstituted C3-C 20 Cycloalkyl group, and substituted or unsubstituted C3-C 20 One selected from the group consisting of aryl groups, and in the above substituted or unsubstituted, the substituent is independently at least one selected from the group consisting of a halogen group, a cyano group, a nitro group, and a C1-C8 alkyl group, R 10 and R 11 are each independently straight-chain C1-C 20 alkyl group, p is an integer from 0 to 4), [Chemical Formula 7] Al(R 13 ) p X 3-p (In the above chemical formula 7, R 13 Silver hydrogen atom, substituted or unsubstituted C1-C 20 Alkyl group, substituted or unsubstituted C3-C 20 Cycloalkyl group, and substituted or unsubstituted C3-C 20 One selected from the group consisting of aryl groups, X is a halogen atom, p is an integer from 0 to 3, and In the above substitution or non-substitution, the substituent is independently at least one selected from the group consisting of a halogen group, a cyano group, a nitro group, and a C1-C8 alkyl group.

2. A Ziegler-Natta catalyst for olefin polymerization, wherein in the first paragraph, at least one first internal electron donor is included in the mixture, at least one second internal electron donor is included in the mixture, and at least two third internal electron donors are included in the mixture.

3. A Ziegler-Natta catalyst for olefin polymerization, comprising the mixture in a weight ratio of first internal electron donor > third internal electron donor > second internal electron donor in the first paragraph.

4. A Ziegler-Natta catalyst for olefin polymerization, wherein the first internal electron donor is included in an amount of 50 to 80 wt% of the mixture, the second internal electron donor is included in an amount of 1 to 20 wt% of the mixture, and the third internal electron donor is included in an amount of 10 to 40 wt% of the mixture.

5. In the first paragraph, the mixture is a Ziegler-Natta catalyst for olefin polymerization, which comprises 10 to 20 wt% of the Ziegler-Natta catalyst for olefin polymerization.

6. In the first paragraph, the first internal electron donor represented by the chemical formula 4 is a Ziegler-Natta catalyst for olefin polymerization comprising at least one compound represented by any one of the chemical formulas 4-1 to 4-3 below: [Chemical Formula 4-1] [Chemical Formula 4-2] [Chemical Formula 4-3] 7. In the first paragraph, the second internal electron donor represented by the chemical formula 5 is a Ziegler-Natta catalyst for olefin polymerization, which comprises at least one compound represented by any one of the chemical formulas 5-1 to 5-4 below: [Chemical Formula 5-1] [Chemical Formula 5-2] [Chemical Formula 5-3] [Chemical Formula 5-4] 8. In the first paragraph, the third internal electron donor represented by the chemical formula 6 is a Ziegler-Natta catalyst for olefin polymerization, which comprises at least one compound represented by any one of the chemical formulas 6-1 to 6-3 below: [Chemical Formula 6-1] [Chemical Formula 6-2] [Chemical Formula 6-3] 9. A Ziegler-Natta catalyst for olefin polymerization, wherein the titanium compound of the Ziegler-Natta main catalyst for olefin polymerization and the external electron donor are included in a molar ratio of 1:3 to 1:9 in the first paragraph.

10. In the first paragraph, the external electron donor is a substituted or unsubstituted C3-C, one of L3 and L4 in the chemical formula 3. 20 A first external electron donor which is a cycloalkyl group, in which both L3 and L4 in the above chemical formula 3 are substituted or unsubstituted C3-C 20 A Ziegler-Natta catalyst for olefin polymerization, comprising at least one second external electron donor that is a cycloalkyl group.

11. A Ziegler-Natta catalyst for olefin polymerization, wherein the external electron donor is the second external electron donor in the 10th paragraph.

12. In the 10th paragraph, the first external electron donor is represented by the chemical formula 3-1 below, and the second external electron donor is represented by the chemical formula 3-2 below, a Ziegler-Natta catalyst for olefin polymerization: [Chemical Formula 3-1] [Chemical Formula 3-2] 13. A method for producing polyolefin, comprising a step of polymerizing an olefin monomer in the presence of a Ziegler-Natta catalyst for olefin polymerization according to any one of claims 1 to 12.

14. In the 13th paragraph, the Ziegler-Natta catalyst for olefin polymerization is 1 x 10 for 1 mol of the olefin monomer. -5 3 x 10 -5 A method for producing polyolefin, comprising:

15. Manufactured by the manufacturing method of Article 13, and having an MFR ratio (MFR 21.6 / MFR 2.16 ) is 20 to 25, characterized in that the polyolefin resin.

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