KR20170073446A - Metallocene compound, catalyst system for olefin polymerization comprising the metallocene compound and method for preparing polyolefin with the catalyst system - Google Patents

Abstract

The present invention relates to metallocene catalysts for olefin polymerization and a process for producing polyolefins using the same. The metallocene catalysts according to the invention enable the production of polyolefins with a low molecular weight and a broad molecular weight distribution, but also with a short side chain distribution, such as by copolymerization, even with homopolymerization using them.

Description

TECHNICAL FIELD [0001] The present invention relates to a metallocene compound, a catalyst system for olefin polymerization including the same, and a process for producing a polyolefin using the catalyst system. BACKGROUND ART < RTI ID = 0.0 >

The present invention relates to a metallocene compound, a catalyst system for olefin polymerization including the same, and a process for producing a polyolefin using the catalyst system.

This application claims the benefit of priority based on Korean Patent Application No. 10-2015-0182246, filed on December 18, 2015, the entire contents of which are incorporated herein by reference.

The catalyst system for olefin polymerization can be classified into a Ziegler-Natta catalyst system and a metallocene catalyst system. Both of these catalyst systems have been developed to suit their respective characteristics.

Since Ziegler-Natta catalyst was invented in the 1950s, it has been widely applied to existing commercial processes. However, since the Ziegler-Natta catalyst is a multi-active catalyst having a plurality of active sites, it is difficult to control the physical properties of the polymer such that a polymer having uneven composition distribution of the comonomer is obtained.

The metallocene catalyst system consists of a combination of the main catalyst, which is the main component of the transition metal compound, and the cocatalyst, which is the main component of aluminum, which is a homogeneous complex catalyst and a single active site catalyst. Accordingly, metallocene catalyst systems enable the formation of polymers with narrow molecular weight distributions and uniform compositional distribution of comonomers. Further, the metallocene catalyst system has properties that can change the stereoregularity, copolymerization properties, molecular weight, crystallinity, etc. of the polymer by changing the structure and polymerization conditions of the ligand.

The anthra-metallocene compound is an organometallic compound containing two ligands connected to each other by a bridge group. The bridge group prevents the rotation of the ligand and determines the activity and structure of the metal center.

These anisometallocene compounds are used as catalysts in the production of olefinic homopolymers or copolymers. It is known that anthra-metallocene compounds, especially those containing cyclopentadienyl-fluorenyl ligands, can produce high molecular weight polyethylene. It is also known that an anhydride-metallocene compound containing an indenyl ligand can produce a polyolefin having excellent activity and improved stereoregularity.

On the other hand, in order to produce a polyolefin having excellent processability, a catalyst system capable of forming a low molecular weight polyolefin is required. To this end, there have been many attempts to control the microstructure of polyolefins using hybrid supported catalyst systems. However, hybrid supported catalyst systems are relatively difficult to prepare and have a high manufacturing cost.

In order to control the density of the polyolefin, a method of using a linear alpha-olefin such as 1-hexene as a comonomer is main. However, in order to produce a polyolefin having a high content of comonomer, there is a limit in that the cost of the comonomer is a large part of the manufacturing cost.

The present invention is to provide a metallocene catalyst for olefin polymerization which enables the production of polyolefins having high molecular weight and a broad molecular weight distribution while exhibiting high activity. In particular, the present invention is to provide metallocene compounds which enable the production of polyolefins having a short side chain distribution, such as by homopolymerization alone, by copolymerization.

The present invention also provides a catalyst system for olefin polymerization comprising the metallocene compound.

The present invention also provides a process for producing a polyolefin using the catalyst system.

According to the present invention there is provided a metallocene compound represented by the following general formula

[Chemical Formula 1]

In Formula 1,

X ¹ and X ² are identical to or different from each other;

A is carbon, silicon or germanium;

R ¹ and R ^{1 '} are each independently alkyl having 1 to 20 carbon atoms substituted with alkoxy having 1 to 20 carbon atoms;

R ² , R ³ , R ⁴ , R ⁵ , R ^{2 '} , R ^3' , R ^{4 '} and R ^5' each independently represents hydrogen, alkyl having 1 to 20 carbon atoms, alkenyl having 2 to 20 carbon atoms, Alkylsilyl having 1 to 20 carbon atoms, silylalkyl having 1 to 20 carbon atoms, alkoxysilyl having 1 to 20 carbon atoms, ether having 1 to 20 carbon atoms, silyl ether having 1 to 20 carbon atoms, alkoxy having 1 to 20 carbon atoms, Aryl, alkylaryl having 7 to 20 carbon atoms, or arylalkyl having 7 to 20 carbon atoms;

R ⁶ and R ⁷ are each independently an alkyl having 1 to 20 carbon atoms or an alkenyl having 2 to 20 carbon atoms.

According to the present invention, there is provided a catalyst system for olefin polymerization comprising the metallocene compound.

According to the present invention, there is also provided a process for producing a polyolefin comprising polymerizing at least one olefin monomer containing ethylene in the presence of the catalyst system.

Hereinafter, a metallocene compound, a catalyst system for olefin polymerization including the same, and a method for producing a polyolefin using the catalyst system according to embodiments of the present invention will be described in detail.

Prior to that, and unless explicitly stated throughout the present specification, the terminology is used merely to refer to a specific embodiment and is not intended to limit the present invention.

And, the singular forms used herein include plural forms unless the phrases expressly have the opposite meaning. Means that a particular feature, region, integer, step, operation, element and / or component is specified, and that other specific features, regions, integers, steps, operations, elements, components and / And the like.

The term " racemic form " as used herein refers to a form in which the same substituent on two cyclopentadienyl moieties is on the plane containing the transition metal and on the opposite side of the center of the cyclopentadienyl moiety it means.

The term " meso form " as used herein means that the same substituent on two cyclopentadienyl moieties is in the same plane on the plane containing the transition metal and on the center of the cyclopentadienyl moiety it means.

I. Metallocene  compound

According to one embodiment of the invention, there is provided a metallocene compound represented by the following formula 1:

[Chemical Formula 1]

In Formula 1,

X ¹ and X ² are identical to or different from each other;

A is carbon, silicon or germanium;

R ¹ and R ^{1 '} are each independently alkyl having 1 to 20 carbon atoms substituted with alkoxy having 1 to 20 carbon atoms;

R ² , R ³ , R ⁴ , R ⁵ , R ^{2 '} , R ^3' , R ^{4 '} and R ^5' each independently represents hydrogen, alkyl having 1 to 20 carbon atoms, alkenyl having 2 to 20 carbon atoms, Alkylsilyl having 1 to 20 carbon atoms, silylalkyl having 1 to 20 carbon atoms, alkoxysilyl having 1 to 20 carbon atoms, ether having 1 to 20 carbon atoms, silyl ether having 1 to 20 carbon atoms, alkoxy having 1 to 20 carbon atoms, Aryl, alkylaryl having 7 to 20 carbon atoms, or arylalkyl having 7 to 20 carbon atoms;

R ⁶ and R ⁷ are each independently an alkyl having 1 to 20 carbon atoms or an alkenyl having 2 to 20 carbon atoms.

The metallocene compound represented by Formula 1 is an anthra-metallocene structure compound having two indenyl groups as a ligand.

In particular, the inventors of the present invention have found that the metallocene compound represented by the above formula (1) has the above-described structure (in particular, the role of Lewis base as an oxygen-giving site at the positions of R ¹ and R ^{1 '} , It is possible to produce a polyolefin having a low molecular weight and a broad molecular weight distribution while exhibiting high activity in the polymerization of olefins.

In particular, the metallocene compound of formula (1) enables the production of a polyolefin having a short chain branching distribution such as by copolymerization by homopolymerization using the metallocene compound. For example, the ethylene homopolymer prepared by using the compound of Formula 1 as a catalyst has a short side chain in the molecule, and can exhibit properties and properties similar to those of an ethylene / 1-butene copolymer.

Further, the metallocene compound of the above formula (1) enables introduction of a side chain at a higher ratio in the molecule during the olefin copolymerization using the metallocene compound.

According to an embodiment of the present invention, in Formula 1, X ¹ and X ² may be the same or different halogen, preferably chloro (Cl), respectively.

In the above formula (1), A is a bridge group connecting two indenyl groups, and may be a group 14 element, preferably carbon, silicon or germanium, and more preferably silicon.

In Formula 1, R ¹ and R ^{1 '} are each independently an alkyl having 1 to 20 carbon atoms substituted with an alkoxy having 1 to 20 carbon atoms, preferably 6-tert-butoxyhexyl.

Wherein R ² , R ³ , R ⁴ , R ⁵ , R ^{2 '} , R ^3' , R ^{4 '} and R ^5' are each independently selected from the group consisting of hydrogen, alkyl having 1 to 20 carbon atoms, Alkylsilyl having 1 to 20 carbon atoms, silylalkyl having 1 to 20 carbon atoms, alkoxysilyl having 1 to 20 carbon atoms, ether having 1 to 20 carbon atoms, silyl ether having 1 to 20 carbon atoms, alkoxy having 1 to 20 carbon atoms Aryl having 6 to 20 carbon atoms, alkylaryl having 7 to 20 carbon atoms, or arylalkyl having 7 to 20 carbon atoms; Preferably each hydrogen or alkyl having 1 to 20 carbon atoms.

Wherein R ⁶ and R ⁷ are each independently an alkyl having 1 to 20 carbon atoms or an alkenyl having 2 to 20 carbon atoms; Preferably each may be methyl.

As a non-limiting example, representative examples of the metallocene compound represented by the above formula (1) are as follows:

[Formula 1-1]

.

.

Meanwhile, the metallocene compound represented by Formula 1 can be synthesized by the following method.

Step 1 is a step of reacting a compound of formula (a) with a compound of formula (b) to prepare a compound of formula (c). The reaction of Step 1 can be carried out at a temperature of -200 to 0 캜 using alkyllithium (for example, n-butyllithium) as a catalyst, and toluene, THF and the like can be used as a solvent. At this time, after separating the organic layer from the product, it is preferable to dry the separated organic layer in vacuo to remove excess reactant.

Step 2 is a step of reacting a compound of formula (c) with a compound of formula (d) to prepare a compound of formula (1). The reaction of Step 2 can be carried out at a temperature of -200 to 0 캜 using an alkyllithium (for example, n-butyllithium) as a catalyst, and ether, hexane and the like can be used as a solvent.

In Step 2, the compound of Chemical Formula 1 is obtained as a mixture of racemic form and meso form. If necessary, the racemic or meso form compound may be selectively removed from the mixture by a method of subjecting the mixture of isomers to a selective recrystallization treatment in a solvent such as toluene, benzene, dichloromethane and the like at a temperature of -20 ° C to room temperature Can be separated.

II. Catalyst systems for olefin polymerization

According to another embodiment of the present invention, there is provided a catalyst system for olefin polymerization comprising the metallocene compound described above.

The metallocene compound represented by the above formula (1) can be applied to the catalyst system for olefin polymerization by itself or together with the cocatalyst.

For example, the catalyst system for olefin polymerization may further include at least one cocatalyst selected from the group consisting of compounds represented by the following formulas (2) to (4):

(2)

^{- [Al (R 21) -O} ] c -

In Formula 2,

c is an integer of 2 or more,

Each R ²¹ is independently halogen, a hydrocarbyl of 1 to 20 carbon atoms, or a hydrocarbyl of 1 to 20 carbon atoms substituted by halogen;

(3)

D ( ^R31 ) ₃

In Formula 3,

D is aluminum or boron,

R ³¹ is each independently halogen, a hydrocarbyl of 1 to 20 carbon atoms or a hydrocarbyl of 1 to 20 carbon atoms substituted by halogen;

[Chemical Formula 4]

[LH] ⁺ [Q (E) ₄ ] ^-

In Formula 4,

L is a neutral Lewis base,

[LH] ⁺ is Bronsted acid,

Q is boron or aluminum in the +3 type oxidation state,

E each independently represent a hydrogen atom of at least one of which is substituted by halogen, a hydrocarbyl of 1 to 20 carbon atoms, an alkoxy or phenoxy functional group, aryl of 6 to 20 carbon atoms, or alkyl of 1 to 20 carbon atoms.

Specifically, the compound represented by Formula 2 may be an alkyl aluminoxane such as methyl aluminoxane, ethyl aluminoxane, butyl aluminoxane, or isobutyl aluminoxane. As the compound of Formula 2, modified methyl aluminoxane (MMAO), which is a compound in which a part of the methyl groups of methyl aluminoxane are substituted with other alkyl groups, may be used. For example, the modified methylaluminoxane may be a compound in which 40 mol% or less, or 5 mol% to 35 mol%, of the methyl group in the methylaluminoxane is substituted with a linear or branched alkyl group having 3 to 10 carbon atoms. Examples of the commercially available modified methylaluminoxane include MMAO-12, MMAO-3A and MMAO-7.

The compound represented by the general formula (3) is preferably selected from the group consisting of trimethylaluminum, triethylaluminum, triisobutylaluminum, tripropylaluminum, tributylaluminum, dimethylchloroaluminum, dimethylisobutylaluminum, dimethylethylaluminum, diethylchloroaluminum, Propyl aluminum, triisobutyl aluminum, tri-s-butyl aluminum, tricyclopentyl aluminum, tripentyl aluminum, triisopentyl aluminum, trihexyl aluminum, ethyl dimethyl aluminum, methyldiethyl aluminum, Dimethylaluminum ethoxide, trimethylboron, triethylboron, triisobutylboron, tripropylboron, tributylboron, and the like can be used.

In addition, the compound represented by the above-mentioned general formula (4) may be used in combination with triethylammonium tetraphenylboron, tributylammoniumtetraphenylboron, trimethylammoniumtetraphenylboron, tripropylammoniumtetraphenylboron, trimethylammoniumtetra (p- Boron, triethylammoniumtetra (o, p-dimethylphenyl) boron, trimethylammoniumtetra (o, p-dimethylphenyl) boron, tributylammoniumtetra (p (P-trifluoromethylphenyl) boron, tributylammonium tetrapentafluorophenylboron, N, N-diethylanilinium tetraphenylboron, N, N- Diethylanilinium tetraphenylboron, N, N-diethylanilinium tetrapentafluorophenylboron, diethylammonium tetrapentafluorophenylboron, triphenylphosphonium tetraphenylboron, trimethylphosphonium tetra (P-tolyl) aluminum, trimethylammonium tetraphenyl aluminum, trimethylammonium tetraphenyl aluminum, trimethylammonium tetraphenyl aluminum, trimethylammonium tetraphenyl aluminum, tributylammonium tetraphenyl aluminum, (p-tolyl) aluminum, triethylammoniumtetra (o, p-dimethylphenyl) aluminum, tributylammoniumtetra (ptrifluoromethylphenyl) aluminum, trimethylammoniumtetra (ptrifluoromethylphenyl) aluminum , Tributylammonium tetrapentafluorophenyl aluminum, N, N-diethylanilinium tetraphenyl aluminum, N, N-diethylanilinium tetraphenyl aluminum, N, N-diethylanilinium tetrapentafluoride Phenyl aluminum, diethylammonium tetrapentafluorophenyl aluminum, triphenylphosphonium tetraphenyl aluminum, trimethylphosphonium tetraphenyl alu (P-trifluoromethylphenyl) boron, triphenylcarbonium tetrapentafluorophenylboron, and the like can be used in combination. have.

Preferably, the co-catalyst includes trimethyl aluminum, triethyl aluminum, triisopropyl aluminum, triisobutyl aluminum, ethylaluminum sesquichloride, At least one compound selected from the group consisting of diethylaluminum chloride, ethyl aluminum dichloride, methylaluminoxane, and modified methylaluminoxane is preferably used. Can be applied.

The content of the cocatalyst may be determined in consideration of catalytic activity and the like. As an example, the cocatalyst may be included in a molar ratio of 1: 1 to 1: 10000, or 1: 1 to 1: 5000, or 1: 1 to 1: 3000, relative to the metallocene compound.

According to an embodiment of the present invention, the catalyst system may be a supported catalyst system in which the metallocene compound (or the metallocene compound and a cocatalyst) is supported on a carrier.

The carrier may be one having a hydroxyl group on its surface and preferably having a hydroxyl group and a siloxane group which are dried and have moisture removed from the surface and have high reactivity. As a non-limiting example, the carrier may be one or more inorganic materials selected from the group consisting of silica, silica-alumina and silica-magnesia, dried at high temperature. And, the carrier may contain oxides such as Na ₂ O, carbonates such as K ₂ CO ₃ , sulphates such as BaSO _4, and nitrate salts such as Mg (NO ₃ ) ₂ .

According to an embodiment of the invention, in the catalyst system, the metallocene compound may be supported in a mass ratio of 1: 0.001 to 1: 1 with respect to the support. That is, when the carrier and the metallocene compound are contained at the mass ratio, they exhibit appropriate catalytic activity and may be advantageous in terms of maintenance of catalytic activity and economical efficiency.

On the other hand, the above-mentioned supported catalyst system can be prepared by a method comprising supporting a promoter on a support and supporting the support with the metallocene compound represented by the formula (1). Examples of the preparation of the supported catalyst system include hydrocarbon solvents such as pentane, hexane and heptane; Or an aromatic solvent such as benzene or toluene may be used.

III. Process for producing polyolefin

According to another embodiment of the invention, there is provided a process for producing a polyolefin comprising polymerizing at least one olefin monomer comprising ethylene in the presence of the catalyst system described above.

The process for producing the polyolefin is carried out using the above-described catalyst system, thereby enabling the production of a polyolefin having a low molecular weight and a broad molecular weight distribution, and a short side chain distribution such as by homopolymerization, especially by homopolymerization. Further, the process for producing the polyolefin is carried out using the catalyst system described above, so that olefin copolymerization enables the production of a polyolefin having a side chain introduced at a higher ratio into the molecule.

The polyolefin prepared by the above method is expected to exhibit not only excellent processability but also improved environmental stress cracking resistance by satisfying all the above-mentioned characteristics.

According to an embodiment of the invention, the process for preparing the polyolefin can be carried out by applying the conventional apparatus and contact technique as raw materials to at least one olefin monomer including ethylene in the presence of the catalyst system described above.

As a non-limiting example, the process for preparing the polyolefin may be carried out by homopolymerizing ethylene or copolymerizing ethylene with comonomers using a continuous slurry polymerization reactor, a loop slurry reactor, a gas phase reactor, or a solution reactor. Examples of the comonomer include propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, -Tetradecene, 1-hexadecene, 1-aidocene and the like can be used.

In the above production method, the catalyst system may be used in a state of being dissolved or diluted in a solvent such as pentane, hexane, heptane, nonane, decane, toluene, benzene, dichloromethane, chlorobenzene and the like.

The production method of the polyolefin is carried out at a temperature of 20 to 500 ° C or 20 to 200 ° C and a pressure of 1 to 100 kgf / cm 2 or 1 to 70 kgf / cm 2 for 1 to 24 hours or 1 to 10 hours .

If necessary, the polymerization may be carried out under hydrogenation or non-addition conditions.

The metallocene catalysts according to the invention enable the production of polyolefins with a low molecular weight and a broad molecular weight distribution, but also with a short side chain distribution, such as by copolymerization, even with homopolymerization using them.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. However, the following embodiments are intended to illustrate the invention, but the invention is not limited thereto.

Example 1

[Step 1]

3.2 g (12 mmol) of 3-tether indene (Formula a) was placed in a 250 ml Schlenk flask and 50 ml of ether was introduced under argon. After cooling the solution to 0 ° C, 5.6 ml (14 mmol) of 2.5 M n-BuLi hexane solution was added dropwise. After cooling the lithiated 3-tether indene solution to -78 ° C, 0.774 g (6 mmol) of dimethyldichlorosilane (Si (CH ₃ ) ₂ Cl ₂ ) was added dropwise. The mixture was stirred at room temperature for one day. After stirring for one day, 50 ml of water was added to the flask and quenched. The organic layer was separated and dried with MgSO ₄ . As a result, a ligand (chemical formula c) of 3.4 g (5.7 mmol, 95%, yellow oil) was obtained.

NMR standard purity (wt%) = 100%, Mw = 600.99

¹ H NMR (500 MHz, CDCl ₃ ): -0.53, -0.35, -0.09 (6H, t), 1.18 (18H, m), 1.41 (8H, m), 1.54 m), 7.28 (4H, m), 3.32 (4H, m), 6.04 (1H, s), 6.26 ).

[Step 2]

To the oven, 250 ml of Schlenk flask I was charged with 4 equivalents of methyl tert-butyl ether (MTBE) and toluene in a solvent. 2.1 equivalents of n-BuLi solution was added and lithiated until the next day.

2.1 equivalents of ZrCl ₄ (THF) ₂ in a glove box was placed in a 250 ml Schlenk flask II and ether was added to the suspension.

Both flasks were cooled to -78 ° C and ligand anion (Schlenk flask I) was slowly added to the Zr suspension (Schlenk flask II). After the injection, the reaction mixture was slowly warmed to room temperature. This was stirred for one day, then filtered under argon, and both the filtered solid and the filtrate were evaporated under reduced pressure.

The catalyst synthesis was confirmed by NMR analysis on the remaining filter cake and filtrate, and the yield and purity were checked by weighing and sampling in the glove box. As a result, a catalyst precursor of 3.6 g (5.58 mmol, 98.02%, Formula 1-1) was obtained from 3.4 g (5.7 mmol) of the ligand and stored in toluene solution (2.0723 g / mmol).

NMR standard purity (wt%) = 100%, Mw = 641.05

^{1 H NMR (500 MHz, CDCl} 3): 0.87 (6H, m), 1.14 (18H, m), 1.11-1.59 (16H, m), 2.61, 2.81 (4H, m), 3.30 (4H, m), (1H, s), 5.57 (1H, s), 5.74 (1H, s), 6.88 (1H, m), 7.02 -7.71 (1 H, m).

Example 2

Silica (manufactured by Grace Davison, XPO 2412) was dewatered and dried under vacuum at a temperature of 300 ° C for 12 hours.

20 g of dried silica was placed in a glass reactor, and methylaluminoxane (MAO) solution containing 13 mmol of aluminum in toluene solution was added to the glass reactor and reacted slowly at 40 ° C for 1 hour with stirring. And washed several times with a sufficient amount of toluene until the unreacted aluminum compound was completely removed. Subsequently, the remaining toluene was removed by depressurization at 50 DEG C to obtain 32 g of MAO supported carrier. The obtained MAO / SiO ₂ was found to contain 17% Al.

12 g of the MAO supported carrier was placed in a glass reactor, and then 70 ml of toluene was added thereto and stirred. A toluene solution in which 1 mmol (based on zirconium) of the metallocene compound obtained in Example 1 was dissolved was added thereto, and the mixture was reacted at 40 ° C for 2 hours. Subsequently, the resultant was washed with a sufficient amount of toluene and hexane, and then vacuum-dried to obtain a supported catalyst as a solid powder.

Example 3

The supported catalyst obtained in Example 2 was quantitated in a glove box, packed in a 50 ml glass bottle, sealed with a rubber septum, and taken out from a glove box to prepare a catalyst to be injected.

A 600 ml metal alloy reactor equipped with a temperature controllable mechanical stirrer was prepared. 400 ml of a hexane solution containing 1.0 mmol of triethylaluminum and the prepared catalyst were introduced into the reactor without air contact, and then the gaseous ethylene monomer was continuously added at a pressure of 9 kgf / cm ² at 80 ° C and stirred for 1 hour .

After the stirring was stopped, unreacted ethylene was removed by evacuation to terminate the polymerization. After removing the polymerization solvent by filtration, the polymer was dried in a vacuum oven at 80 DEG C for 4 hours to obtain a polymer.

Example 4

A polymer was obtained in the same manner as in Example 3 except that 4 g of 1-butene was fed into the reactor together with the gaseous ethylene monomer.

Example 5

A polymer was obtained in the same manner as in Example 3 except that 4 g of 1-hexene was fed into the reactor together with the gaseous ethylene monomer.

Comparative Example 1

[Chemical formula C-1]

A supported catalyst was obtained in the same manner as in Example 2 except that the compound represented by the above formula (C-1) was used instead of the metallocene compound represented by the above formula (1-1).

Then, a polymer was obtained in the same manner as in Example 3 except that the supported catalyst was used.

Comparative Example 2

A polymer was obtained in the same manner as in Comparative Example 1, except that 4 g of 1-butene was injected into the reactor together with the gaseous ethylene monomer.

Comparative Example 3

A polymer was obtained in the same manner as in Comparative Example 1, except that 4 g of 1-hexene was fed into the reactor together with the gaseous ethylene monomer.

Comparative Example 4

[Chemical formula C-2]

A supported catalyst was obtained in the same manner as in Example 2 except that the compound represented by the above formula (C-2) was used instead of the metallocene compound represented by the above formula (1-1).

Then, a polymer was obtained in the same manner as in Example 3 except that the supported catalyst was used.

Comparative Example 5

A polymer was obtained in the same manner as in Comparative Example 4, except that 4 g of 1-hexene was fed into the reactor together with the gaseous ethylene monomer.

Comparative Example 6

[Formula C-3]

A supported catalyst was obtained in the same manner as in Example 2, except that the compound represented by the above formula (C-3) was used instead of the metallocene compound represented by the above formula (1-1).

Then, a polymer was obtained in the same manner as in Example 3 except that the supported catalyst was used.

Comparative Example 7

A polymer was obtained in the same manner as in Comparative Example 6, except that 4 g of 1-butene was fed into the reactor together with the gaseous ethylene monomer.

Test Example

The following properties were measured in the production of the respective polymers according to Examples 3 to 5 and Comparative Examples 1 to 7, and the results are shown in Tables 1 to 3 below.

(1) Catalytic activity: Calculated as the ratio of the weight (g) of the polymer produced per g of the catalyst content (g) based on the unit time (h).

(2) Weight average molecular weight (Mw) and molecular weight distribution (PDI) of the polymer: The weight average molecular weight (Mw) and the number average molecular weight (Mn) of the polymer were measured using gel permeation chromatography (GPC, , And the molecular weight distribution (PDI) was calculated by dividing the weight average molecular weight by the number average molecular weight. At this time, the analysis temperature was 160 캜, trichlorobenzene was used as a solvent, and the molecular weight was measured by standardizing with polystyrene.

(3) Types and content of side chains: The kind and content (% by weight) of side chains introduced into the polymer by ¹ H NMR were analyzed. At this time, the polymer sample was dissolved in a solvent of 1,1,2,2-tetrachloroethane-d ₂ at a high temperature and analyzed at 110 ° C., and a Bruker DMX 600 MHz NMR / BBFO ( ¹ H / ¹⁹ F / Broad band) probe and an Agilent 500 MHz NMR / Dual probe was used.

Example 3 Example 4 Example 5 Catalyst compound (1-1) (1-1) (1-1) Ethylene feed O O O 1-Butene feed X O X 1-Hexene feed X X O Catalyst content (mg) 10 10 10 Catalytic activity
(g Pol./g Cat. * hr) 3.3 4.3 2.2 Mw 53,300 44,000 50,000 PDI 6.7 4.1 5.7 1-C4 incorporation,
C2 branches (wt%) 2 2.5 2.2 1-C6 incorporation,
C4 branches (wt%) 0 0 1.9 > 1-C8 incorporation,
> C6 branches (wt%) 0 1.3 0.1

Comparative Example 1 Comparative Example 2 Comparative Example 3 Catalyst compound The compound of formula C-1 The compound of formula C-1 The compound of formula C-1 Ethylene feed O O O 1-Butene feed X O X 1-Hexene feed X X O Catalyst content (mg) 10 10 10 Catalytic activity
(g Pol./g Cat. * hr) 5.0 2.5 3.5 Mw 111,300 76,000 90,600 PDI 2.7 2.1 2.4 1-C4 incorporation,
C2 branches (wt%) 0 1.4 0 1-C6 incorporation,
C4 branches (wt%) 0 0 0.5 > 1-C8 incorporation,
> C6 branches (wt%) 0 1.0 0

Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 Catalyst compound The compound of formula C-2 The compound of formula C-2 The compound of formula C-3 The compound of formula C-3 Ethylene feed O O O O 1-Butene feed X X X O 1-Hexene feed X O X X Catalyst content (mg) 10 10 10 10 Catalytic activity
(g Pol./g Cat. * hr) 2.8 1.2 6.3 3.7 Mw 119,800 134,200 98,200 60,200 PDI 2.4 2.5 2.4 3.1 1-C4 incorporation,
C2 branches (wt%) 0 1.1 0 4.5 1-C6 incorporation,
C4 branches (wt%) 0 0 0 0 > 1-C8 incorporation,
> C6 branches (wt%) 0 1.0 0 0.8

Referring to Tables 1 to 3, in Examples 3 to 5 using the catalyst compound of Formula 1-1, a polymer having a low molecular weight and a broad molecular weight distribution was obtained as compared with Comparative Examples.

In particular, it was confirmed that the ethylene homopolymer having a short side chain distribution similar to that of ethylene / alpha-olefin copolymer was produced in the case of Example 3 above, despite ethylene homopolymerization.

In the ¹ H NMR analysis of the ethylene homopolymer according to Comparative Example 1, Comparative Example 4 and Comparative Example 7, only the terminal -CH ₃ peak due to ethylene homopolymerization was observed as in the theory. On the other hand, in the ¹ H NMR analysis of the ethylene homopolymer according to Example 3, the -CH ₃ peak of the C2 branche terminal which can be exhibited by the incorporation of 1-butene was observed.

Claims (12)

A metallocene compound represented by the following formula (1):
[Chemical Formula 1]

In Formula 1,
X ¹ and X ² are identical to or different from each other;
A is carbon, silicon or germanium;
R ¹ and R ^{1 '} are each independently alkyl having 1 to 20 carbon atoms substituted with alkoxy having 1 to 20 carbon atoms;
R ² , R ³ , R ⁴ , R ⁵ , R ^{2 '} , R ^3' , R ^{4 '} and R ^5' each independently represents hydrogen, alkyl having 1 to 20 carbon atoms, alkenyl having 2 to 20 carbon atoms, Alkylsilyl having 1 to 20 carbon atoms, silylalkyl having 1 to 20 carbon atoms, alkoxysilyl having 1 to 20 carbon atoms, ether having 1 to 20 carbon atoms, silyl ether having 1 to 20 carbon atoms, alkoxy having 1 to 20 carbon atoms, Aryl, alkylaryl having 7 to 20 carbon atoms, or arylalkyl having 7 to 20 carbon atoms;
R ⁶ and R ⁷ are each independently an alkyl having 1 to 20 carbon atoms or an alkenyl having 2 to 20 carbon atoms.
The method according to claim 1,
And R < ¹ & gt ^; are each 6-tert-butoxyhexyl.
The method according to claim 1,
Wherein R ² , R ³ , R ⁴ , R ⁵ , R ^{2 '} , R ^3' , R ^{4 '} and R ^5' are each independently hydrogen or alkyl of 1 to 20 carbon atoms.
The method according to claim 1,
And X < ^{1 >} and X < ² > are each chloro.
The method according to claim 1,
Wherein A is silicon.
The method according to claim 1,
Wherein R < ⁶ > and R < ⁷ > are each methyl.
The method according to claim 1,
The compound is a metallocene compound represented by the formula:

.
A catalyst system for olefin polymerization comprising a metallocene compound according to claim 1.
9. The method of claim 8,
Wherein the metallocene compound is supported on at least one carrier selected from the group consisting of silica, silica-alumina and silica-magnesia.
Polymerizing at least one olefin monomer comprising ethylene in the presence of the catalyst system according to claim 8
≪ / RTI >
11. The method of claim 10,
Wherein the polyolefin is an ethylene homopolymer.
12. The method of claim 11,
Wherein the ethylene homopolymer has a short side chain of 2 to 2 carbon atoms in the molecule of from 0.1 to 5% by weight.