KR20200060066A - Preparing method of catalyst for polymerization of polyolefin - Google Patents

Abstract

The present invention relates to a method for preparing a catalyst for polyolefin synthesis, and more particularly to a method for preparing a catalyst for polyolefin synthesis, comprising steps of: reacting a carrier and a transition metal compound; and reacting a carrier, a compound represented by the following formula 1, a compound represented by the following formula 2, or an internal electron donor, which is a combination thereof. In the formulas 1 and 2, R^1 to R^18 are the same as defined in the specifications.

Description

Manufacturing method of catalyst for polyolefin synthesis {PREPARING METHOD OF CATALYST FOR POLYMERIZATION OF POLYOLEFIN}

The present invention relates to a method for preparing a catalyst for synthesizing polyolefins, and more specifically, to provide a catalyst for synthesizing polyolefins having improved catalytic activity while using an eco-friendly internal electron donor and having excellent particle regularity of synthesized polyolefins. It's about how.

Polyethylene, which is widely used among polyolefins, is classified into low density polyethylene and high density polyethylene according to density and performance. High density polyethylene has excellent softening point, hardness, strength, and electrical insulation, and is mainly used for various containers, packaging films, fibers, pipes, packings, and insulating materials. In particular, high-density polyethylene has excellent mechanical properties, excellent chemical resistance and electrical insulation properties, and is inexpensive, and is used as a material for secondary battery separators.

Meanwhile, the catalyst used to produce the polyolefin may be divided into a Ziegler-Natta catalyst, a chromium catalyst, and a metallocene catalyst depending on the type of the central metal to be applied. Since these catalysts have different catalytic activity, hydrogen reactivity, molecular weight distribution, and reaction properties to comonomers, they have been selectively used depending on the manufacturing process and the required characteristics of the application product. Among these, Ziegler-Natta catalysts containing magnesium have advantages in terms of high activity, operational stability, excellent physical properties, and economical efficiency compared to other catalysts, and thus are most used in the production of polyolefin polymers.

The Ziegler-Natta catalyst directly affects the properties and properties of the polyolefin produced according to its composition, structure and manufacturing method. Therefore, in order to change the properties of the resulting polyolefin, changes in the components of the catalyst, the structure of the carrier, and the method of preparing the catalyst must be accompanied in the production of the catalyst. Research on the activity of the catalyst, the molecular weight of the polymerized polymer, and stereoregularity should also be conducted in parallel. As described above, in the polyolefin polymerization, a method of using a phthalate-based compound as an internal electron donor or coagulant to improve the physical properties of the resulting polymer by lowering the cost through increasing catalytic activity and improving catalyst performance such as stereoregularity It is widely known. For example, Japanese Laid-Open No. 1993-001112 reports a method of manufacturing a magnesium complex compound (MCC) using magnesium and halogen organic compounds and preparing a solid catalyst using the same, and using phthalate as an internal electron donor. have. However, the phthalate-based compound is a type of 'endocrine disrupter' that enters the body of an animal or human and interferes with or disrupts the action of hormones. It has been found to have adverse effects on humans and ecosystems, such as triggers, and is now banned.

Accordingly, although many studies have been conducted to synthesize a compound for replacing the phthalate-based compound with an internal electron donor, phthalate-based compounds such as phthalic anhydride or phthalic chloride have been mainly used as flocculants. Therefore, there is still a need to develop a Ziegler-Natta solid catalyst for polyolefin synthesis, which includes an eco-friendly flocculant and an internal electron donor, exhibits high polymerization activity, and can produce polymers with excellent stereoregularity.

One aspect of the present invention is to provide a method capable of preparing a catalyst capable of synthesizing a polyolefin having excellent catalytic activity and excellent particle regularity while including an eco-friendly internal electron donor compound.

According to one aspect of the invention, the step of supporting the carrier and the transition metal compound; And a carrier, a compound represented by the following formula (1), a compound represented by the following formula (2) or a combination thereof, an electron donor compound is provided. In the following formulas 1 and 2, R ¹ to R ¹⁸ are as defined in the specification.

[Formula 1] [Formula 2]

According to the present invention, there is provided a method for preparing a catalyst for polyolefin polymerization using a keto ester-based and a diether-based internal electron donor as an eco-friendly internal electron donor, obtained by a method for preparing a polyolefin synthesis catalyst of the present invention The catalyst is environmentally friendly and has a physical property equal to or greater than that of a process using a conventional phthalate-based compound, and polyolefins having excellent particle regularity can be synthesized.

Hereinafter, preferred embodiments of the present invention will be described. However, embodiments of the present invention may be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below.

The present invention relates to a method for preparing a catalyst capable of synthesizing a polyolefin having excellent physical properties and having properties equal to or greater than a process using a conventional phthalate-based compound while using an environmentally friendly internal electron donor. The method for preparing a catalyst for synthesizing a polyolefin of the present invention comprises the steps of supporting a carrier and a transition metal compound; And supporting a carrier and an internal electron donor compound that is a compound represented by Formula 1, a compound represented by Formula 2, or a combination thereof.

[Formula 1]

In Chemical Formula 1,

R ¹ to R ¹⁴ are each independently hydrogen, a straight-chain or branched (C ₁ -C ₂₀ ) alkyl group, (C ₂ -C ₂₀ ) alkenyl group, (C ₃ -C ₂₀ ) cycloalkyl group, (C ₆ -C ₂₀ ) Aryl group, (C ₁ -C ₂₀ ) alkylsilyl group, (C ₇ -C ₂₀ ) arylalkyl group, (C ₇ -C ₂₀ ) alkylaryl group, (C ₂ -C ₂₀ ) heteroalkyl group substituted with hetero atom And a (C ₅ -C ₂₀ ) heteroaryl group substituted with a hetero atom;

 [Formula 2]

In Chemical Formula 2,

R ¹⁵ and R ¹⁸ are each independently hydrogen, a straight-chain or branched (C ₁ -C ₂₀ ) alkyl group,

R ¹⁶ and R ¹⁷ are each independently hydrogen, a straight-chain or branched (C ₁ -C ₂₀ ) alkyl group, (C ₂ -C ₂₀ ) alkenyl group, (C ₃ -C ₂₀ ) cycloalkyl group, (C ₆ -C ₂₀ ) Aryl group, (C ₁ -C ₂₀ ) alkylsilyl group, (C ₇ -C ₂₀ ) arylalkyl group, (C ₇ -C ₂₀ ) alkylaryl group, (C ₂ -C ₂₀ ) heteroalkyl group substituted with hetero atom , Heteroaryl group substituted with a hetero atom (C ₅ -C ₂₀ ).

When R ¹ to R ¹⁸ in Formula 1 is an ether alkyl group substituted with a hetero atom or a heteroaryl group, the hetero atom may be one or more selected from the group consisting of S, N, O, Si, P, and B. .

In the present specification, a cycloalkyl group means a monovalent functional group derived from cycloalkane, and an aryl group means a monovalent or divalent functional group derived from an aromatic hydrocarbon arene. Further, the alkylsilyl group means a silyl group substituted with an alkyl group, the arylalkyl group refers to an alkyl group substituted with an aryl group, and the alkylaryl group refers to an aryl group substituted with an alkyl group.

In the catalyst composition for polyolefin polymerization, the internal electron donor can be used together with a transition metal compound to increase the activity of the catalyst in the polyolefin polymerization reaction and to improve the stereoregularity and hydrogen reactivity of the polyolefin to be produced. .

In more detail, the 2-alkoxy-cyclohexane carboxylate compound of Formula 1 may be introduced as an ether group and an ester group to act as a donor that is a Lewis base. That is, the compound structure of Formula 1 is not harmful to the environment and the human body and is eco-friendly, and has excellent steric regularity and high melt index. In addition, the ether structure of the diether-based compound of Formula 2 has excellent stereoregularity and high melt index. Accordingly, the internal electron donor comprising the compound of Formula 1, the compound of Formula 2, or a combination thereof can effectively increase the activity of the catalyst in the polyolefin polymerization reaction, and produce a polyolefin excellent in high hydrogen reactivity and stereoregularity. .

Preferred internal electron donors, the compound of formula 1 of the present invention, for example, 2-methoxy-cyclohexane methyl ester, 2-methoxy-cyclohexane ethyl ester, 2-methoxy-cyclohexane propyl ester, 2-methoxy -Cyclohexanebutyl ester, 2-methoxy-cyclohexanehexyl ester, 2-methoxy-cyclohexane isopropyl ester, 2-methoxy-cyclohexane isobutyl ester, 2-methoxy-cyclohexane benzyl ester, 2- Methoxy-cyclohexane cyclohexyl ester, 2-ethoxy-cyclohexane methyl ester, 2-ethoxy-cyclohexane ethyl ester, 2-ethoxy-cyclohexane propyl ester, 2-ethoxy-cyclohexane butyl ester, 2 -Ethoxy-cyclohexanehexyl ester, 2-ethoxy-cyclohexane isopropyl ester, 2-ethoxy-cyclohexane isobutyl ester, 2-ethoxy-cyclohexane benzyl ester, 2-ethoxy-cyclohexane cyclohexyl Ester, butoxy-cyclohexane methyl ester, 2-butoxy-cyclohexane ethyl ester, 2-butoxy-cyclohexane propyl ester, 2-butoxy-cyclohexanebutyl ester, 2-butoxy-cyclohexanehexyl ester, 2-Butoxy-cyclohexane isopropyl ester, 2-butoxy-cyclohexane isobutyl ester, 2-butoxy-cyclohexane benzyl ester, 2-butoxy-cyclohexane cyclohexyl ester, 2-propoxy-cyclohexane Methyl ester, 2-Protoxy-cyclohexane ethyl ester, 2-Protoxy-cyclohexane propyl ester, 2-Protoxy-cyclohexane butyl ester, 2-Protoxy-cyclohexanehexyl ester, 2-Protoxy-cyclohexane Isopropyl ester, 2-Protoxy-cyclohexane isobutyl ester, 2-Protoxy-cyclohexane benzyl ester, 2-Protoxy-cyclohexane cyclohexyl ester, 2-Isoprotoxy-cyclohexane methyl ester, 2- Iso Protoxy-cyclohexane ethyl ester, 2-isoprotoxy-cyclohexanepropyl ester, 2-isoprotoxy-cyclohexanebutyl ester, 2-isoprotoxy-cyclohexanehexyl ester, 2-isoprotoxy-cyclohexaneiso Propyl ester, 2-isopropoxy-cyclohexaneisobutyl ester, 2-isopropoxy-cyclohexanebenzyl ester, 2-isobutoxy- Cyclohexane methyl ester, 2-isobutoxy-cyclohexaneethyl ester, 2-isobutoxy-cyclohexanepropyl ester, 2-isobutoxy-cyclohexanebutyl ester, 2-isobutoxy-cyclohexanehexyl ester, 2 -Isobutoxy-cyclohexane isopropyl ester, 2- isobutoxy-cyclohexane isobutyl ester, 2- isobutoxy-cyclohexane benzyl ester, 2- isobutoxy-cyclohexane cyclohexyl ester, and the like. , One or two or more of them can be used as an internal electron donor. Among them, it is preferable to use 2-methoxy-cyclohexane isobutyl ester, 2-ethoxy-cyclohexane isobutyl ester, etc. from the viewpoint of providing excellent stereoregularity.

Preferred internal electron donors, the compound of formula 2 of the present invention, for example, 2,2-dicyclopentyl-1,3-dimethoxypropane, 2,2-dicyclohexyl-1,3-dimethoxypropane, 2, 2-diisobutyl-1,3-dimethoxypropane, 2,2-isopropyl-1,3-dimethoxypropane, 2,2-diisopentyl-1,3-dimethoxypropane, 2,2-di Phenyl-1,3-dimethoxypropane, 2,2-dibenzyl-1, 3-dimethoxypropane, 2,2-bis (cyclohexylmethyl) 1,3-dimethoxypropane, 2,2-diisobutyl -1,3-dimethoxypropane, 2,2-diisobutyl-1,3-ethoxypropane, 2-ethyl-2-butyl-1,3-dimethoxypropane, 2-ethyl-2-isopropyl- 1,3-dimethoxypropane, 2-ethyl-2-isopentyl-1,3-dimethoxypropane, 2-ethyl-2-isobutyl-1,3-dimethoxypropane, 2-ethyl-2'-phenyl -1,3-dimethoxypropane, 2-ethyl-2-benzyl-1,3-dimethoxypropane, 2-ethyl-2-cyclopentyl-1,3-dimethoxypropane, 2-ethyl-2-cyclohexyl -1,3-dimethoxypropane, 2-methyl-2-isopropyl-1, 3-dimethoxypropane, 2-methyl-2-butyl-1,3-dimethoxypropane, 2-methyl-2-phenyl- 1,3-dimethoxypropane, 2-methyl-2-benzyl-1,3-dimethoxypropane, 2-methyl-2-cyclopentyl-1,3-dimethoxypropane, 2-methyl-2-cyclohexyl- 1,3-dimethoxypropane, 2-methyl-2-isopropyl-1,3-dimethoxypropane, 2-methyl-2-isopentyl-1,3-dimethoxypropane, 2-isopropyl-2-butyl -1,3-dimethoxypropane, 2-isopropyl-2-isopentyl-1,3-dimethoxypropane, 2-isopropyl-2-isobutyl-1,3-dimethoxypropane, 2-isopropyl- 2-phenyl-1,3-dimethoxypropane, 2-isopropyl-2-benzyl-1,3-dimethoxypropane, 2-isopropyl-2-cyclopentyl-1,3-dimethoxypropane, 2-iso Propyl-2-cyclohexyl-1,3-dimethoxypropane, 2-isobutyl-2-butyl-1,3-dimethoxypropane, 2-isobutyl-2-isopentyl-1,3-dimethoxypropane, 2-isobutyl-2-phenyl-1,3-dimethoxypropane, 2-isobutyl-2-benzyl-1,3-dimethoxypropane, 2-isobutyl-2-cyclopentyl-1,3-dimethoxy Propane, 2-isobutyl-2 -Cyclohexyl-1,3-dimethoxypropane, 2-isopentyl-2-butyl-1,3-dimethoxypropane, 2-isopentyl-2-phenyl-1,3-dimethoxypropane, 2-isopentyl -2-benzyl-1,3-dimethoxypropane, 2-isopentyl-2-cyclopentyl-1,3-dimethoxypropane, and 2-isopentyl-2-cyclohexyl-1,3-dimethoxypropane, etc. And the like, and may be used as an internal electron donor by mixing one or two or more of them.

The internal electron donor of the present invention may be a compound represented by Formula 1, a compound represented by Formula 2, or a combination thereof.

In addition, in addition to the compound of Formula 1, various internal electron donor compounds known in the art, for example, a succinate compound, a silane compound, a fluorene compound, or a mixture thereof may be further included.

The internal electron donor is preferably added in an amount of 0.001 to 0.017 mol based on 1 mol of the transition metal compound, and more preferably 0.003 to 0.01 mol. If the content of the internal electron donor is less than 0.001 mol based on 1 mol of the transition metal compound, the content of the internal electron donor may be too small to decrease the activity and stereoregularity, and if it exceeds 0.017 mol, the activity of the catalyst is lowered, which is undesirable. .

When the internal electron donor compound is a combination of a compound represented by the following formula (1) and a compound represented by the following formula (2), the content ratio thereof is 0.1 based on 1 mole of the compound represented by the formula (1). It is preferably from 10 to 10 mol, more preferably from 0.2 to 5 mol. When the compound represented by Formula 2 is less than 0.1 based on 1 mole of the compound represented by Formula 1, the stereoregularity of the polyolefin may be lowered, and when it exceeds 10 moles, a narrow molecular weight distribution may be exhibited.

Preferably, the supported molar ratio of the internal electron donor and the carrier may be 0.05: 1 to 1: 1, preferably 0.1: 1 to 0.2: 1 based on 1 mole of the carrier. The internal electron donor serves to increase the activity of the catalyst in the polymerization reaction and to improve the stereoregularity of the synthesized polyolefin. When the content of the internal electron donor is too small compared to the content of the carrier, the stereoregularity is Can not be controlled, and if the content of the internal electron donor is too large, the activity of the catalyst may be low.

The carrier that can be used for preparing the catalyst for polyolefin polymerization of the present invention comprises fixing or supporting the transition metal compound and the internal electron donor, in the present invention, supporting the carrier and the transition metal compound; And the step of supporting the carrier and the internal electron donor compound may be performed sequentially, in reverse order, or simultaneously. On the other hand, it is more preferable to increase the catalytic activity when the carrier and the transition metal compound are first supported to form an active point, and then an internal electron donor is introduced and supported. In addition, when the combination of the compound of Formula 1 and the compound of Formula 2 is used as an internal electron donor, the steps for supporting them are also not limited, and the compound of Formula 1, compound of Formula 2, or compound of compound 2 may be supported simultaneously or simultaneously.

For example, in one embodiment of the present invention, the reactant comprising the transition metal compound and the internal electron donor, one or more carriers selected from the group consisting of magnesium compounds, silica, alumina, zeolites and hybrid carriers thereof It can be supported and supported on a carrier.

There is no particular limitation on the carrier, and a carrier known to be commonly used in the preparation of general Ziegler-Natta catalysts can be prepared without limitation, or commercially available. Preferably, the carrier may be one comprising at least one component selected from the group consisting of silica, alumina, silica-alumina, zeolite and magnesium compounds, mixtures thereof or hybrid carriers thereof may also be used, more Preferably, a magnesium compound can be used. The hybrid carrier refers to a state in which two or more kinds of silica, alumina, zeolite, and magnesium compounds react or are combined.

Specific examples of the magnesium compound include dihalogenated magnesium, dialkoxy magnesium, alkylmagnesium halide, alkoxymagnesium halide, or aryloxymagnesium halide, and the like, and when using dihalogenated magnesium or dialkoxymagnesium as a carrier, the activity of the catalyst And stereoregularity of the synthesized polyolefin.

As a specific example of the transition metal compound that can be used in the present invention, any transition metal compound known to be used as a Ziegler Natta catalyst for polyethylene polymerization can be used without limitation. In particular, preferred examples of the transition metal compound include a compound of Formula 3 below.

[Formula 3]

MX _n (OR ¹⁹ ) _{4 -n}

In Chemical Formula 3, M is selected from the group consisting of transition metal elements of the periodic table IVB, VB and VIB, X is selected from a halogen atom, R ¹⁹ is (C ₁ -C ₁₀ ) alkyl group, n is a metal Oxidized water is 0 to 4.

Preferred examples of the M include Ti, Zr, Hf, Rf, V, Nb, Ta, Db, Cr, Mo, W, Sg, and the like, and a transition metal compound containing one or more of them may be used. In addition, specific examples of the transition metal compound of Chemical Formula 3 include titanium tetrachloride, titanium tetrabromide, titanium iodide, tetrabutoxy titanium, tetraethoxy titanium, diethoxy titanium dichloride, zirconium tetrachloride, chromium chloride or ethoxy titanium Trichloride and the like, and it is preferable to use zirconium tetrachloride [Zirconium (IV) chloride], chromium chloride [Chromium (III) chloride], titanium tetrachloride, or a combination thereof.

On the other hand, the halogen atom X may be fluorine (Fluorine), chlorine (Chlorine), bromine (Bromine) or iodine (Iodine).

The transition metal compound may be included in an amount of 0.1% to 10% by weight, for example, 2.1% to 10% by weight based on the total catalyst weight. When the content of the transition metal compound is less than 0.1% by weight, the activity of the catalyst for polyolefin polymerization may decrease, and when the content of the transition metal compound is excessive, the content of the internal electron donor decreases, resulting in a decrease in stereoregularity. have.

The supported molar ratio of the transition metal compound and the carrier may be 3: 1 to 30: 1, preferably 9: 1 to 20: 1 based on 1 mole of the carrier. When the content of the transition metal compound is too small compared to the content of the carrier, the catalyst performance may be deteriorated due to the small amount of the transition metal compound exhibiting catalytic activity, and when the content of the transition metal compound is too large compared to the content of the carrier, the magnesium compound In comparison, excessive amounts of transition metal components are present in the catalyst, which is undesirable in process economy.

In the step of supporting the carrier and the transition metal compound, it is preferable that the transition metal compound is slowly added to the carrier over 10 minutes to 2 hours. Meanwhile, the step of supporting the carrier and the transition metal compound is preferably performed at -30 to 50 ° C, for example, -25 to -10 ° C. If the temperature is less than -30 ° C, the supporting temperature is too low to complete the reaction, and if it exceeds 50 ° C, the particle shape of the catalyst may be destroyed and process stability may be lowered.

On the other hand, the temperature of the step of supporting the carrier and the transition metal compound may be gradually increased, starting at a temperature of -50 to 50 ℃.

And, the step of supporting the internal electron donor compound represented by the following formula (1) is preferably carried out at a temperature of -20 to 150 ℃. If the temperature is less than -20 ° C, the reaction is difficult to complete, and if it exceeds 150 ° C, the polymerization activity and stereoregularity of the resulting catalyst may be lowered by side reaction, which is not preferable.

The internal electron donor is to be introduced during or during the process of heating from the reaction temperature of the step of supporting the carrier and the transition metal compound to the temperature of the step of supporting the transition metal compound with the internal electron donor. Can be. At this time, the input temperature, the number of inputs, and the input time are not greatly limited.

Meanwhile, the reaction temperature in the step of simultaneously supporting the transition metal compound and the internal electron donor is preferably 0 ° C or more and less than 100 ° C.

Polyethylene can be synthesized in the presence of a catalyst prepared using the method for preparing a catalyst for synthesizing polyethylene of the present invention, and polyethylene can be synthesized in the presence of a catalyst system further comprising a co-catalyst or an external electron donor in the catalyst. Can be.

The timing of introducing the co-catalyst is not particularly limited, but it is preferable to add it after the step of supporting the carrier, the transition metal compound and the internal electron donor, as it can increase the activity of the catalyst.

On the other hand, the timing of injecting the external electron donor is also not particularly limited, but it is preferable to inject it after the step of supporting the carrier, the transition metal compound and the internal electron donor, as in the case of a cocatalyst, as it can increase the activity of the catalyst.

The cocatalyst can reduce the transition metal compound to form an active point, thereby enhancing catalytic activity. The cocatalyst according to an embodiment has no particular limitation, and any organometallic compound known to be used in the preparation of a general polyethylene synthesis catalyst can be used without limitation. Especially, it is preferable to use the alkyl aluminum compound represented by following formula (4).

[Formula 4]

AlR ²⁰ _n X _{3 -n}

In Chemical Formula 4, R ²⁰ is a (C ₁ -C ₈ ) alkyl group, X is halogen, and n is 0 to 3.

Specific examples of the co-catalysts are trimethyl aluminum, triethyl aluminum, triisobutyl aluminum, tributyl aluminum, diethyl aluminum dichloride, ethyl aluminum dichloride, ethyl aluminum sesquichloride, tripropyl aluminum, tributyl aluminum, tripentyl aluminum , Trihexyl aluminum, trioctyl aluminum, and the like, and one or more of them can be selected and used.

In addition, the cocatalyst may be introduced in an amount of 0.01 to 10 moles per mole of the transition metal compound, and may be 1: 0.01 to 1: 2. If the amount of the co-catalyst is too small or too large, the activity of the catalyst may decrease.

The step of injecting the cocatalyst can be performed at -30 to 100 ° C, and particularly preferably 0 to 30 ° C. In addition, it is preferable that the contact time is sufficiently contacted for 0.5 to 24 hours from the time when the reaction is made.

In addition, the catalyst for polymerization of the polyolefin may further include an external electron donor, and the external electron donor can be used without particular limitation as long as it is an external electron donor commonly used for polyolefin synthesis, but the catalyst for polyolefin synthesis of the present invention The manufacturing method of may further include the step of reacting with a silane-based external electron donor represented by the formula (5).

[Formula 5]

SiR ²¹ _n (OR ²² ) _4-n

In Formula 5, R ²¹ and R ²² are each independently hydrogen, a straight-chain or branched (C ₁ -C ₁₀ ) alkyl group, (C ₃ -C ₁₀ ) cycloalkyl group, (C ₆ -C ₂₀ ) aryl group, (C ₁ -C ₁₀ ) Aminoalkyl group and (C ₂ -C ₁₀ ) alkoxyalkyl group, and n is 0 to 4.

Specific examples of the external electron donor, cyclic hexyl methyl dimethoxysilane, dicyclic pentyl dimethoxysilane, diisopropyl dimethoxysilane, vinyl triethoxysilane, triethylmethoxysilane, trimethylethoxysilane, dicyclo Pentyldiethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, diphenyldiethoxysilane, phenylpropyldimethoxysilane, pentyltrimethoxysilane, tertiarybutyltrimethoxysilane, cyclichexylethyldimethoxysilane , Cyclichexylmethyldimethoxysilane, cyclicpentyltriethoxysilane, diisobutyldiethoxysilane, isobutyltriethoxysilane, normalpropyltrimethoxysilane, isopropyltrimethoxysilane, cyclicheptylmethyldiethoxy Silane, dicycloheptyldiethoxysilane, and the like, and one or more of them may be selected and used.

In the catalyst for polyolefin polymerization, the internal electron donor reacts with the co-catalyst of Chemical Formula 4 to remove a part, and an external electron donor is combined with the vacancy to proceed with the polymerization reaction. Therefore, the role of the external electron donor in the polyolefin polymerization catalyst is similar to that of the internal electron donor. That is, it is possible to effectively increase the activity of the catalyst in the polyolefin polymerization reaction and to increase the stereoregularity in the polymerization of the olefin.

The external electron donor can be reacted in an amount of 0.01 to 10 moles per mole of the transition metal compound, and preferably 1: 0.01 to 1: 2. If the use amount of the external electron donor is too small outside the above range, complementation of activity and stereoregularity may be insignificant, and when excessively large, the activity of the catalyst may be deteriorated.

The step of reacting with the external electron donor can be performed at -30 to 100 ° C, particularly preferably 0 to 30 ° C.

The co-catalyst or the external electron donor can be reacted by dispersing in a hydrocarbon solvent as necessary. Specific examples of the hydrocarbon solvent include aliphatic or alicyclic (C ₅ -C ₂₀ ) hydrocarbons, and among them, aliphatic or alicyclic (C ₆ -C ₁₇ ) hydrocarbon solvents are preferred. More specific examples include aliphatic hydrocarbons such as hexane, heptane, octane, decane, dodecane, tetradecane and mineral oil; Alicyclic hydrocarbons such as cyclic hexane, cyclic octane, methyl cyclic pentane, and methyl cyclic hexane; And aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, and cumene. It is more preferable to use hexane in order to have a uniform particle size distribution of the prepared solid catalyst and a smooth spherical surface of the catalyst particle.

The catalyst for synthesizing polyolefin of the present invention may be a catalyst in a solid form, and may have an average diameter of 5 μm to 100 μm, or 5 μm to 70 μm. The average diameter of the catalyst for polyolefin polymerization refers to the average diameter of a plurality of catalyst solid particles for polyolefin polymerization.

When the average diameter of the polyolefin polymerization catalyst is reduced to less than 5 μm, it is difficult to generate a smooth flow in the reactor because the size of the polyolefin polymerization catalyst is not sufficiently secured. It can reduce the driving stability of the catalyst and reduce the mileage of the catalyst.

Furthermore, the catalyst for polyolefin polymerization of the present invention, in addition to the internal electron donor, the transition metal compound, the carrier, the co-catalyst, the external electron donor, etc. as described above, in addition to the excipients or additives commonly employed in the technical field to which the present invention pertains It can contain as.

According to another aspect of the present invention, the step of manufacturing a catalyst for synthesizing polyolefins by the method for preparing a catalyst for synthesizing polyolefins of the present invention as described above; And in the presence of the catalyst obtained by the step of preparing the catalyst, comprising the step of polymerizing an olefin-based monomer, a method for producing a polyolefin is provided.

The polyolefin synthesized in this way is an environmentally friendly and improved polymer that does not use phthalate-based compounds harmful to the human body and the environment as internal electron donors in the manufacturing process, so that no phthalate compounds remain in the polymer.

At this time, the polyolefin synthesis reaction may be in a gas phase, a liquid phase, or a solution phase. When performing a synthetic reaction in a liquid phase, a hydrocarbon solvent may be used, or the olefin itself may be used as a solvent.

The synthesis temperature may be 0 to 200 ° C, and a range of 30 to 150 ° C is preferred. When the synthesis temperature is less than 0 ° C, the activity of the catalyst is poor, and when it exceeds 200 ° C, the stereoregularity is poor, which is not preferable. The synthesis pressure can proceed at 1 to 100 atmospheres, and it is preferable to proceed at 2 to 40 atmospheres. When the synthetic pressure exceeds 100 atm, it is not desirable from an industrial and economic standpoint. The synthesis reaction can be carried out by any of batch, semi-continuous, and continuous methods.

On the other hand, the polyolefin prepared by using the solid catalyst according to the present invention can be added to the thermal stabilizer, light stabilizer, flame retardant, carbon black, pigment, antioxidant, etc. are usually added. In addition, the prepared polyolefin may be used by mixing linear low density polyethylene (LLDPE), low density polyethylene (LDPE), high density polyethylene (HDPE), EP (ethylene / propylene) rubber, and the like.

In the present invention, the olefin monomer is ethylene, propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene, 1-undecene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-aitocene, norbornene, norbornadiene, ethylidene novoden, phenyl novoden, vinyl novoden, dicyclopentadiene, 1,4-butadiene , 1,5-pentadiene, 1,6-hexadiene, styrene, alpha-methyl styrene, divinylbenzene, and 3-chloromethylstyrene.

As described above, according to the present invention, not only has a high activity and apparent density in a polyolefin polymerization reaction, but also allows for easy control of the particle size and distribution, molecular weight distribution, etc. of the polyolefin to be produced, thereby improving mechanical properties and processability for secondary battery separators. It is possible to obtain a method for producing a polyolefin polymerization catalyst capable of producing a polyolefin and a method for producing a polyolefin using the same.

Hereinafter, the present invention will be described in more detail through specific examples. The following examples are only examples for helping the understanding of the present invention, and the scope of the present invention is not limited thereto.

Example

1. Preparation of catalyst and synthesis of polyethylene

<Example 1>

1. Preparation of solid catalyst

180 mL of titanium tetrachloride was placed in a nitrogen-circulated reactor, and after cooling to a temperature lower than -20 ° C, 13 g of a magnesium carrier was added and stirred. After maintaining at the same temperature for about 1 hour, the temperature of the reactor was gradually raised to 80 ° C. After the temperature was raised to 80 ° C, 1.4 g of 2-methoxy-cyclohexane methyl ester and 0.6 g of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane were added. Furthermore, after the temperature was raised to 120 ° C., the mixture was stirred at the same temperature for 1 hour, stirring was stopped, and the supernatant was removed. After washing twice using 180 mL of titanium tetrachloride at the same temperature, and then washing 5 times using 200 mL hexane each time at 70 ° C., a solid catalyst was obtained as a catalyst composition for polyolefin polymerization.

2. Polymerization of polyethylene

The 2 liter high pressure reactor heated to 120 ° C. was purged with nitrogen for 1 hour to make the state of the high pressure reactor into a nitrogen atmosphere. Under a nitrogen atmosphere, the temperature of the reactor was lowered to 25 ° C. and purged with propylene to keep the reactor in a propylene atmosphere. In a reactor maintained in a propylene gas atmosphere, 2 mmol of triethylaluminum diluted in a decane solvent was added at a concentration of 1 mol, and the cyclohexylmethyldimethoxysilane external electron donor diluted in a decane solvent had a Si / Ti mole ratio of 30. Input. 5 mg of the solid catalyst, 1000 ml of hydrogen, and 500 g of propylene were added and the stirrer was operated to perform prepolymerization for 5 minutes. After pre-polymerization, the temperature of the reactor was heated to 70 ° C and polymerization was performed at 70 ° C for 1 hour. Table 1 shows the measurement results of the properties of the catalyst after polymerization.

<Example 2>

Solid as in Example 1, except that 0.93 g of 2-methoxy-cyclohexane methyl ester and 1.3 g of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane were used as the internal electron donor. A catalyst was prepared, and polypropylene was polymerized using the same method as in Example 1.

<Example 3>

Solid in the same manner as in Example 1, except that 0.5 g of 2-methoxy-cyclohexane methyl ester and 1.9 g of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane were used as the internal electron donor. A catalyst was prepared, and polypropylene was polymerized using the same method as in Example 1.

<Example 4>

A solid catalyst was prepared in the same manner as in Example 1, except that only 1.9 g of 2-methoxy-cyclohexane methyl ester was used as the internal electron donor, and polypropylene was polymerized in the same manner as in Example 1 using the same. .

<Comparative Example 1>

A solid catalyst was prepared in the same manner as in Example 1, except that only 2.5 g of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane was used as the internal electron donor. Polypropylene was polymerized in the same manner.

<Comparative Example 2>

A solid catalyst was prepared in the same manner as in Example 1, except that 1.6 g of diisobutyl phthalate was used as the internal electron donor, and polypropylene was polymerized in the same manner as in Example 1 using the same.

2. Measurement of physical properties of catalyst and polypropylene

The properties of the catalyst and polypropylene prepared in Examples and Comparative Examples were measured in the following manner and are shown in Table 1.

Experimental Example 1: Catalytic activity measurement

The weight of the polymer (Kg) prepared for 1 hour per weight (g) of the catalyst used in the Examples and Comparative Examples was measured.

Experimental Example 2: Measurement of stereoregularity of polypropylene

Prepare 200 ml xylene in the flask and filter with 200 mm No. 4 extract paper. The aluminum pan was dried for 30 minutes in a 150 ° C. oven and cooled in a desiccator to measure mass. Next, 100 ml of filtered o-xylene was collected with a pipette, transferred to an aluminum pan, and heated to 145 to 150 ° C to evaporate all o-xylene. Thereafter, the aluminum pan was dried under vacuum at a temperature of 100 ± 5 ° C. and a pressure of 1 hr, 13.3 kPa for 1 hour. After the aluminum pan was cooled in a desiccator, the above process was repeated twice to complete the o-xylene-only blank test within a weight error of 0.0002 g.

Next, after drying each polymer obtained in Examples and Comparative Examples (70 ° C., 13.3 kPa, 60 minutes, vacuum drying), 2 g ± 0.0001 g of a polymer sample cooled in a desiccator was placed in a 500 ml flask, and 200 ml o-xylene was added. Nitrogen and cooling water were connected to the flask, and the flask was heated for 1 hour to continuously reflux o-xylene. Thereafter, the flask was placed in the air for 5 minutes, cooled to 100 ° C. or less, and the flask was shaken and placed in a constant temperature bath (25 ± 0.5 ° C.) for 30 minutes to precipitate insoluble matter. The resulting liquid was precipitated and filtered repeatedly until it was clean with 200 mm No. 4 extract paper. After drying at 150 ° C for 30 minutes, after cooling in a desiccator, 100 ml of the filtered solution was added to an aluminum pan weighed in advance, and the aluminum pan was heated to 145 to 150 ° C to evaporate o-xylene. The evaporated aluminum pan was vacuum dried for 1 hour at a temperature of 70 ± 5 ° C. and a pressure of 13.3 kP, and the process of cooling in a desiccator was repeated twice to measure the weight within an error of 0.0002 g.

As shown in Equation 1 below, the weight percentage (Xs) of the portion of the resulting polymer dissolved in o-xylene was obtained, and the weight ratio (= 100-Xs) of the polymer not extracted in o-xylene was obtained therefrom. Later, this was referred to as a three-dimensional rule diagram (XI).

* Three-dimensional rule diagram (XI) = 100- Xs [calculation formula 1]

Experimental Example 3: Measurement of melt index (MI) of polypropylene

By ASTM1238, the amount of resin extruded at 230 ° C., 2.16 kg for 10 minutes is expressed in g.

Experimental Example 4: Measurement of molecular weight distribution of polypropylene

The molecular weight distribution (MwD) is the ratio (Mw / Mn) of the weight average molecular weight and number average molecular weight measured by gel permeation chromatography, and was measured by gel permeation chromatography according to a method according to DIN 55672. (Solvent: 1,2,4-trichlorobenzene, flow rate: 1ml / min, temperature: 140 ° C)

Active (kg-PP / g-cat, hr) Stereoregularity (wt%) Melt Index (g / 10 min) MwD Example 1 38 2.6 15 6.5 Example 2 42 2.2 15 4.1 Example 3 44 2.0 18 3.9 Example 4 38 3.0 15 6.7 Comparative Example 1 48 1.6 20 3.5 Comparative Example 2 35 2.5 9 4.2

As shown in Table 1, the catalyst prepared according to the embodiment using the compound of the present invention as an internal electron donor has excellent activity, has a high melt index, and is capable of synthesizing polyolefins with improved stereoregularity. Can be confirmed.

Particularly, in the case of the catalyst of the present invention, it exhibits a characteristic of having a higher activity and a broader molecular weight distribution than a phthalate-based catalyst, and such a broad molecular weight distribution can produce various polymerized products, and can lower production costs in the process of molding and processing polymerized products. . Further, the present invention can produce an excellent polyolefin equivalent to or higher than the phthalate-based internal electron donor, which is an environmentally harmful substance.

Although the embodiments of the present invention have been described in detail above, the scope of rights of the present invention is not limited to this, and it is possible that various modifications and variations are possible without departing from the technical spirit of the present invention as set forth in the claims. It will be apparent to those of ordinary skill in the field.

Claims (8)

Supporting a carrier and a transition metal compound; And
Carrying a carrier and an internal electron donor compound which is a compound represented by Formula 1, a compound represented by Formula 2 below, or a combination thereof;
Method for producing a catalyst for synthesizing polyolefins comprising:
[Formula 1]

In Chemical Formula 1,
R ¹ to R ¹⁴ are each independently hydrogen, a straight-chain or branched (C ₁ -C ₂₀ ) alkyl group, (C ₂ -C ₂₀ ) alkenyl group, (C ₃ -C ₂₀ ) cycloalkyl group, (C ₆ -C ₂₀ ) Aryl group, (C ₁ -C ₂₀ ) alkylsilyl group, (C ₇ -C ₂₀ ) arylalkyl group, (C ₇ -C ₂₀ ) alkylaryl group, (C ₂ -C ₂₀ ) heteroalkyl group substituted with hetero atom And a (C ₅ -C ₂₀ ) heteroaryl group substituted with a hetero atom;
[Formula 2]

In Chemical Formula 2,
R ¹⁵ and R ¹⁸ are each independently hydrogen, a straight-chain or branched (C ₁ -C ₂₀ ) alkyl group,
R ¹⁶ and R ¹⁷ are each independently hydrogen, a straight-chain or branched (C ₁ -C ₂₀ ) alkyl group, (C ₂ -C ₂₀ ) alkenyl group, (C ₃ -C ₂₀ ) cycloalkyl group, (C ₆ -C ₂₀ ) Aryl group, (C ₁ -C ₂₀ ) alkylsilyl group, (C ₇ -C ₂₀ ) arylalkyl group, (C ₇ -C ₂₀ ) alkylaryl group, (C ₂ -C ₂₀ ) heteroalkyl group substituted with hetero atom , (C ₅ -C ₂₀ ) heteroaryl group substituted with a hetero atom. The method of claim 1, wherein the internal electron donor compound is introduced in an amount of 0.001 to 0.017 mol based on 1 mol of the transition metal compound. The method according to claim 1, wherein when the internal electron donor compound is a combination of the compound represented by Chemical Formula 1 and the compound represented by Chemical Formula 2, the content ratio thereof is Chemical Formula 2 based on 1 mole of the compound represented by Chemical Formula 1 The compound represented by 0.1 to 10 mol, the method for producing a catalyst for polyolefin synthesis. The method of claim 1, wherein the carrier comprises at least one component selected from the group consisting of silica, alumina, silica-alumina, zeolite, and magnesium compounds. According to claim 1, Supporting the carrier and the transition metal compound; And the step of supporting the carrier and the internal electron donor compound is performed sequentially, in reverse order, or at the same time. The method of claim 1, wherein the transition metal compound comprises a compound of Formula 3 below:
[Formula 3]
MX _n (OR ¹⁹ ) _{4 -n}
In Chemical Formula 3,
M is selected from the group consisting of transition metal elements of group IVB, VB and VIB of the periodic table,
X is halogen,
R ¹⁹ is (C ₁ -C ₁₀ ) alkyl group,
n is 0-4. The method of claim 1, further comprising the step of reacting with a co-catalyst compound represented by the following formula (4):
[Formula 4]
AlR ²⁰ _n X _{3 -n}
In Formula 4,
R ²⁰ is (C ₁ -C ₈ ) alkyl group,
X is halogen,
n is 0-3. The method of claim 1, further comprising the step of reacting with an external electron donor represented by the following formula (5):
[Formula 5]
SiR ²¹ _n (OR ²² ) _4-n
In Chemical Formula 5,
R ²¹ and R ²² are each independently hydrogen, a straight-chain or branched (C ₁ -C ₁₀ ) alkyl group, (C ₃ -C ₁₀ ) cycloalkyl group, (C ₆ -C ₂₀ ) aryl group, (C ₁ -C ₁₀ ) aminoalkyl group and (C ₂ -C ₁₀ ) alkoxyalkyl group,
n is 0-4.