JPH05170820A - Catalyst for polymerization of olefin and polymerization of olefin - Google Patents

Abstract

PURPOSE:To obtain an olefin polymer having a narrow molecular weight distribution and a narrow compositional distribution in high polymerization activity. CONSTITUTION:The title catalyst comprises a transition metal compound of the general formula: CpM(R<1>COCR<2>COR<3>)2X (wherein M is Zr or Hf, Cp is a group containing a cyclopentadienyl skeleton; R<1>, R<2> and R<3> are each a hydrocarbon group; and X is halogen or -SO3CF3) and an organoaluminumoxy compound. The title process comprises polymerizing an olefin in the presence of the above catalyst.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a novel catalyst for olefin polymerization and a method for polymerizing olefins using the catalyst, and more specifically, a catalyst comprising a specific transition metal compound and an organoaluminumoxy compound, and this catalyst. It relates to a method for polymerizing olefins using.

[0002]

BACKGROUND OF THE INVENTION Conventionally, a method for producing an α-olefin polymer has been carried out in the presence of a titanium catalyst comprising a titanium compound and an organoaluminum compound or a vanadium catalyst comprising a vanadium compound and an organoaluminum compound. , A method of copolymerizing ethylene and α-olefin is known.

Generally, an ethylene / α-olefin copolymer obtained with a titanium catalyst has a broad molecular weight distribution and composition distribution, and is inferior in transparency, surface non-adhesiveness and mechanical properties. In addition, the ethylene / α-olefin copolymer obtained with the vanadium catalyst has a narrower molecular weight distribution and composition distribution than those obtained with the titanium catalyst,
And, the transparency, the surface non-tackiness and the mechanical properties are considerably improved, but they are still insufficient for the applications in which these performances are required. -A catalyst that can obtain an α-olefin copolymer is required.

On the other hand, as a new Ziegler type olefin polymerization catalyst, a catalyst comprising a zirconium compound and aluminoxane has been proposed in recent years. For example, JP-A-5
8-19309, JP-A-60-35006, JP-A-60-35007, and JP-A-60-35.
JP-A No. 008, JP-A-61-130314, and JP-A No. 2-41303 disclose transition metal compounds having a pentadienyl group such as a cyclopentadienyl group as a ligand, an alkyl group and / or a halogen atom. It is described that the catalyst system in which the metallocene compound and the aluminoxane are combined is highly active in the polymerization of α-olefin and the obtained polymer has excellent properties.

Also, the Journal of Organometallic Chemis
try, 363 (1989) C12-C14 has Cp ₂ Zr (CF ₃ SO ₃ ).
₂ (THF) and [Cp ₂ Zr (CF ₃ SO ₃ ) (bipy)] ⁺ CF ₃ S
Although O ₃ ⁻ is disclosed, these two compounds have lower olefin polymerization activity than the above-mentioned cyclopentadienyl compound. Further, when the concentration of aluminoxane is low, the olefin polymerization activity is remarkably low.

Under these circumstances, it has been desired to develop a new olefin polymerization catalyst which is excellent in olefin polymerization activity and excellent in properties of the obtained polyolefin.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to provide a novel catalyst for olefin polymerization, and a method for polymerizing olefins using such a catalyst. Is intended to provide.

[0008]

The olefin polymerization catalyst according to the present invention comprises (A) a transition metal compound represented by the following general formula [I], CpM (R ¹ COCR ² COR ³ ) ₂ X ... [I] (formula) Among them, M is zirconium or hafnium.
p is a group having a cyclopentadienyl skeleton and may have a substituent. R ¹ , R ² and R ³ have 1 carbon atom
An alkyl group having 10 to 10, an alkyl group having 1 to 10 carbon atoms substituted with a halogen atom, an aryl group, an aryl group substituted with a halogen atom or an alkyl group, or a furyl group, and R ¹ and R ² are bonded to each other. And may form a ring. X is a halogen atom or -SO ₃ CF ₃
Is. ) (B) An organoaluminum oxy compound.

In the present invention, the transition metal compound is represented by the following general formula [II] CpZr (R ¹ COCR ² COR ³ ) ₂ Cl ... [II] (wherein Cp is a group having a cyclopentadienyl skeleton and is substituted). R ¹ , R ² , and R ³ are each an alkyl group having 1 to 6 carbon atoms, an aryl group, an alkyl group substituted with a halogen atom, or a furyl group, and R ¹
And R ² may combine with each other to form a ring. ) Is preferable, and especially chlorocyclopentadienylbis (2,4-pentadionato)
It is preferably zirconium.

The olefin polymerization method according to the present invention is characterized by polymerizing an olefin in the presence of the above catalyst.

[0011]

DETAILED DESCRIPTION OF THE INVENTION The olefin polymerization catalyst and the olefin polymerization method according to the present invention will be specifically described below.

In the present invention, the term "polymerization" may be used to mean not only homopolymerization but also copolymerization, and the term "polymer" means not only homopolymer but also copolymerization. May be used to mean coalesce.

[Transition Metal Compound] The transition metal compound used in the present invention is a transition metal compound represented by the following general formula [I].

CpM (R ¹ COCR ² COR ³ ) ₂ X [I] In the formula [I], M is zirconium or hafnium. Cp is a cyclopentadienyl group, a methylcyclopentadienyl group, an ethylcyclopentadienyl group, an n-butylcyclopentadienyl group, a dimethylcyclopentadienyl group, a trimethylcyclopentadienyl group, a pentamethylcyclopenta group. Alkyl-substituted cyclopentadienyl group such as dienyl group, or indenyl group,
Fluorenyl group and the like. Of these, a cyclopentadienyl group is preferred.

R ¹ , R ² and R ³ are alkyl groups having 1 to 10 carbon atoms such as methyl group, ethyl group, propyl group, isopropyl group, t-butyl group, trifluoromethyl group, pentafluoroethyl group, An alkyl group having 1 to 10 carbon atoms substituted with a halogen atom such as a heptafluoropropyl group,
A phenyl group, a tolyl group, a p-methoxyphenyl group and the like are aryl groups, aryl groups substituted with halogen atoms or alkyl groups.

R ¹ and R ² may combine with each other to form a ring. X is fluorine, chlorine, bromine,
It is a halogen atom or -SO ₃ CF ₃ iodine.
Of these, preferred is chlorine.

Specific examples of the transition metal compound represented by the general formula [I] include the following compounds. Chlorocyclopentadienylbis (2,4-pentanedionato) -zirconium (IV), chlorocyclopentadienylbis (1,1,1,2,2,3,3-heptafluoro-7,7-
Dimethyl-4,6-octanedionate) -zirconium (I
V), chlorocyclopentadienylbis (1,1,1-trifluoro-2,4-pentanedionato) -zirconium (IV),
Chlorocyclopentadienylbis (1,1,1,5,5,5-hexafluoro-2,4-pentanedionato) -zirconium (I
V), chlorocyclopentadienylbis (4,4,4-trifluoro-1-phenyl-1,3-butanedionate) -zirconium (IV), chlorocyclopentadienylbis (2,2,6,6-
Tetramethyl-3,5-heptanedionato) -zirconium (IV), chlorocyclopentadienylbis (4,4,4-trifluoro-1- (2-furyl) -1,3-butanedionate) -zirconium (IV) , Chlorocyclopentadienylbis (3-
Phenyl-2,4-pentanedionato) -zirconium (I
V), chlorocyclopentadienylbis (1,1,1-trifluoro-5,5-dimethyl-2,4-hexanedionate) -zirconium (IV), chlorocyclopentadienylbis (2-acetylcyclohexene) Sanonato) -zirconium (IV), chlorocyclopentadienylbis (2-acetylcyclopentanonato) -zirconium (IV), chlorocyclopentadienylbis (3-methyl-2,4-pentanedionato) -zirconium (IV), chlorocyclopentadienylbis [1,
3-di (p-methoxyphenyl) -1,3-propanedionate]-
Zirconium (IV), chlorocyclopentadienylbis (1,3-diphenyl-1,3-propanedionat-zirconium (IV), etc.

In the zirconium compound as described above, a transition metal compound in which zirconium metal is replaced with hafnium metal can be used. [Method for producing transition metal compound] The transition metal compound (A) according to the present invention is a compound represented by the following general formula [III] (hereinafter, may be referred to as "compound [III]") and Cp. ₂ MX ₂ ... [III] (In the formula, M, Cp and X are the same as those in the general formula [I].) Β-diketone represented by the following general formula [IV] (hereinafter, referred to as “compound [IV] May be described as).

R ¹ COCHR ² COR ³ ... [IV] (wherein R ¹ , R ² and R ³ are the same as those in the general formula [I].) Such a reaction is represented by the following reaction formula. ..

Cp ₂ MX ₂ + 2R ¹ COCHR ² COR ³ → CpM (R ¹ COCR ² COR ³ ) ₂ X + HX The reaction conditions in these reactions differ depending on the composition of the compound to be obtained, but the compound [IV ] Is the compound [II
I], usually 2 to 100 times mol, preferably 2 to 5 times
Used in a 0-fold molar amount. The reaction temperature is -50 to
It is desirable that the temperature is 180 ° C, preferably 0 to 100 ° C, and the reaction time is 0.1 to 100 hours, preferably 0.1 to 100 hours.
48 hours is desirable.

The transition metal compound used in the present invention may be obtained by contacting the above compound [III] with the compound [IV] in the presence of triethylamine in a solvent. Triethylamine is used in the same amount as the compound [III]. Examples of the solvent used in the reaction include acetonitrile, tetrahydrofuran, ether, benzene, toluene and the like. Such a solvent is generally used in an amount of 1 to 1000 times, preferably 50 to 500 times the amount of the compound [III].

The desired transition metal compound can be produced in good yield by the above production method. The transition metal compound thus obtained can be filtered, and the obtained filtrate can be concentrated under reduced pressure for recrystallization, or can be isolated and purified by a method such as sublimation.

Regarding this reaction, Inorganic Chemistry, 13, 5, 1074-1079
(1974), Inorganic Chemistry
Chemistry), 10,10,2137-2142 (1971), and Inorganic Chemistry, 10,
It is known to 7,1388-1392 (1971).

[Organoaluminumoxy Compound] The organoaluminumoxy compound (B) used as a catalyst for olefin polymerization together with the (A) transition metal compound according to the present invention may be a conventionally known aluminoxane,
Further, it may be a benzene-insoluble organoaluminumoxy compound as exemplified in JP-A-2-78687.

The conventionally known aluminoxane can be produced, for example, by the following method. (1) Compounds containing adsorbed water or salts containing water of crystallization, such as magnesium chloride hydrate, copper sulfate hydrate, aluminum sulfate hydrate, nickel sulfate hydrate, and ceric chloride hydrate A method of recovering a hydrocarbon solution by adding an organoaluminum compound such as trialkylaluminum to the hydrocarbon medium suspension and reacting the same.

(2) A method in which water, ice or steam is directly applied to an organoaluminum compound such as trialkylaluminum in a medium such as benzene, toluene, ethyl ether or tetrahydrofuran to recover it as a hydrocarbon solution.

(3) A method of reacting an organoaluminum compound such as trialkylaluminum with an organotin oxide such as dimethyltin oxide or dibutyltin oxide in a medium such as decane, benzene or toluene.

The aluminoxane may contain a small amount of organic metal component. Alternatively, the solvent or unreacted organoaluminum compound may be removed by distillation from the recovered solution of the aluminoxane, and then redissolved in the solvent.

Specific examples of the organoaluminum compound used for producing a solution of aluminoxane include trimethylaluminum, triethylaluminum, tripropylaluminum, triisopropylaluminum, tri-n-butylaluminum, triisobutylaluminum, trisec. -Butyl aluminum, tri-tert-butyl aluminum, tripentyl aluminum, trihexyl aluminum, trioctyl aluminum, tridecyl aluminum, tricyclohexyl aluminum,
Trialkyl aluminum such as tricyclooctyl aluminum; dimethyl aluminum chloride, diethyl aluminum chloride, diethyl aluminum bromide,
Dialkyl aluminum halides such as diisobutyl aluminum chloride; Dialkyl aluminum hydrides such as diethyl aluminum hydride and diisobutyl aluminum hydride; Dialkyl aluminum alkoxides such as dimethyl aluminum methoxide and diethyl aluminum ethoxide; Dialkyl aluminum aryloxides such as diethyl aluminum phenoxide. To be

Of these, trialkylaluminums are particularly preferred. Further, as the organoaluminum compound, isoprenylaluminum represented by the following general formula [V] can also be used.

[0031] _{(i-C 4 H 9)} x Al y (C 5 H 10) z ... [V] in (formula [IV], x, y, z are positive numbers, z ≧
2x. ) The above-mentioned organoaluminum compounds are used alone or in combination.

As the solvent used in the production of the aluminoxane solution, aromatic hydrocarbons such as benzene, toluene, xylene, cumene and cymene, pentane, hexane, heptane, octane, decane, dodecane, hexadecane, octadecane, etc. Aliphatic hydrocarbons, alicyclic hydrocarbons such as cyclopentane, cyclohexane, cyclooctane and methylcyclopentane, petroleum fractions such as gasoline, kerosene, and light oil, or the above aromatic hydrocarbons, aliphatic hydrocarbons, alicyclics Hydrocarbon halides, in particular, hydrocarbon solvents such as chlorinated compounds and brominated compounds. Other,
Ethers such as ethyl ether and tetrahydrofuran can also be used. Of these solvents, aromatic hydrocarbons are particularly preferable.

The olefin polymerization catalyst according to the present invention is
It can be prepared by mixing (A) a transition metal compound and (B) an organoaluminum oxy compound in an inert hydrocarbon solvent or in an olefin medium. The mixing order at this time is arbitrarily selected.

FIG. 1 shows the steps for preparing the olefin polymerization catalyst according to the present invention. When mixing the catalyst components (A) and (B), the atomic ratio of aluminum of the catalyst component (B) to the transition metal in the catalyst component (A) (Al / transition metal)
Is usually 10 to 10,000, preferably 20 to 5,000.
And the concentration of the catalyst component (A) is in the range of about 10 ⁻⁸ to 10 ⁻¹ mol / liter, preferably 10 ^{−7 to} 5 × 10 ⁻² mol / liter.

[Polymerization Method] The olefin polymerization method according to the present invention comprises the above-mentioned (A) transition metal compound,
(B) The olefin is polymerized in the presence of the organoaluminum oxy compound.

In the present invention, the polymerization can be carried out by either a liquid phase polymerization method such as a slurry polymerization method, a solution polymerization method or a suspension polymerization method, or a gas phase polymerization method. In the liquid phase polymerization, an inert hydrocarbon solvent or olefin itself can be used as a solvent.

Specific examples of the hydrocarbon medium include aliphatic hydrocarbons such as butane, isobutane, pentane, hexane, octane, decane, dodecane, hexadecane and octadecane; cyclopentane, methylcyclopentane,
Alicyclic hydrocarbons such as cyclohexane and cyclooctane; aromatic hydrocarbons such as benzene, toluene and xylene; petroleum fractions such as gasoline, kerosene, and light oil.

In carrying out the slurry polymerization method in the present invention, the polymerization temperature is usually in the range of -50 to 100 ° C, preferably 0 to 90 ° C. When carrying out the liquid phase polymerization method, the polymerization temperature is usually 0 to 250 ° C., preferably 20 to 200 ° C.
When carrying out the gas phase polymerization method, the polymerization temperature is usually 0.
It is desirable to be in the range of 120 to 120 ° C, preferably 20 to 100 ° C.

In the present invention, when the olefin is polymerized by the slurry polymerization method, the solution polymerization method or the gas phase polymerization method,
The transition metal compound (A) has a concentration of the transition metal atom in the polymerization reaction system of usually 10 ^-8 to 10 ^-1 gram atom / liter, preferably 10 ^{-7 to} 5 × 10 ^-2 gram atom / liter. It is preferably used in a quantity. The atomic ratio (Al / transition metal) of the transition metal in the component (A) to the aluminum in the component (B) is usually 10 to 10,000, preferably 20 to 5,000.

The polymerization pressure is usually from normal pressure to 100 kg.
/ Cm ² , preferably under normal pressure to 50 kg / cm ² , and the polymerization can be carried out in any of batch system, semi-continuous system and continuous system. It is also possible to carry out the polymerization in two or more stages under different reaction conditions.

The molecular weight of the obtained olefin polymer can be adjusted by allowing hydrogen to be present in the polymerization system or by changing the polymerization temperature. The olefins that can be polymerized by the olefin polymerization method according to the present invention include ethylene and α-C3-20.
Olefins such as propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1
-Decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene; 3 to 20 carbon atoms
Cyclic olefins such as cyclopentene, cycloheptene, norbornene, 5-methyl-2-norbornene, tetracyclododecene, 2-methyl-1,4,5,8-dimethano-1,2,3,
4,4a, 5,8,8a-octahydronaphthalene and the like can be mentioned. Further, styrene, vinylcyclohexane, diene and the like can be used.

In the present invention, it is possible to copolymerize two or more components using the above-mentioned olefins. For example, ethylene / propylene, ethylene / 1-butene, ethylene / propylene / diene, ethylene / tetracyclododecene and the like.

In the present invention, the above-mentioned (A) transition metal compound and / or (B) organoaluminum oxy compound,
It can also be used by supporting it on a carrier such as silica, alumina, silica-alumina or zirconia.

In the present invention, the olefin may be prepolymerized with the olefin polymerization catalyst upon the polymerization of the olefin. In the prepolymerization, the olefin polymer is 0.05 to 500 g, preferably 0.1 to 300 g, and more preferably 0.2 to 100 g per 1 g of the olefin polymerization catalyst.
Is preferably prepolymerized in an amount of.

As the olefin for the prepolymerization, ethylene and α-olefin having 3 to 20 carbon atoms, such as propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene,
Examples thereof include 1-tetradecene, 3-methyl-1-butene, 3-methyl-1-pentene and the like. Of these, preferred are olefins used during polymerization.

In the present invention, the olefin polymerization catalyst may contain other components useful for olefin polymerization in addition to the above components.

[0047]

According to the olefin polymerization catalyst and the olefin polymerization method of the present invention, an olefin polymer having excellent polymerization activity and having a narrow molecular weight distribution and a narrow composition distribution can be obtained.

[0048]

EXAMPLES The catalyst for olefin polymerization and the method for olefin polymerization according to the present invention will be described in more detail based on the following examples, but the present invention is not limited to these examples.

In the present invention, the intrinsic viscosity [η] is 1
Measured in decalin at 35 ° C. and expressed in dl / g.

[0050]

Example 1 [Preparation of catalyst component (A)] Inner volume 2 fully replaced with nitrogen
Zirconocene dichloride 1 in a 50 ml glass reactor
After charging 0.0 g and heating to 80 ° C., about 50 ml of acetylacetone was slowly added dropwise. In order to remove the generated hydrochloric acid and cyclopentadiene, the operation of degassing for about several seconds and then introducing nitrogen was repeated about every 2 minutes. After dropping, the reaction was continued at 80 ° C. for 15 minutes, and then excess acetylacetone was distilled off under reduced pressure. When the obtained solid was recrystallized from benzene, 7.56 g of chlorocyclopentadienylbis (2,4-pentanedionato) -zirconium (IV) which is a white crystal was obtained (yield; 57%). ..

[Overlap] 50% of internal volume fully replaced with nitrogen
Purified toluene 2 in a 0 ml glass flask
00 ml was added, and the mixture was kept at 60 ° C. for 10 minutes while flowing ethylene at 100 liter / hr.

Next, methylaluminoxane (methylaluminoxane manufactured by Schering Co., which was dried and re-dissolved in toluene) was charged in an amount of 16.2 mg atom in terms of aluminum atom. Further, the zirconium complex was charged at 0.073 mg atom in terms of zirconium atom. After performing polymerization for 20 minutes at 60 ° C., the polymerization was stopped by adding a small amount of methanol.

A small amount of dilute hydrochloric acid was added to the obtained polymer suspension and the mixture was filtered through a glass filter to remove toluene as a solvent, washed with n-hexane, and dried under reduced pressure for 24 hours. The polyethylene obtained was 0.19 g, and the polymerization activity was 700 g / mmol-Zr / hr.

[0054]

Example 2 [Preparation of catalyst component (A)] Inner volume 3 fully replaced with nitrogen
In a 100 ml glass reactor, dry acetonitrile 10
Charge 0 ml and zirconocene dichloride 3.92 g,
Stir until uniform. To this reaction solution, 90 ml of a dry acetonitrile solution containing 4.97 g of dipivaloylmethane and 1.88 ml of triethylamine was added dropwise at room temperature. Further, the reaction was continued at room temperature for 40 hours. The produced white solid was filtered with a glass filter under a nitrogen stream and washed with acetonitrile. The obtained filtrate was concentrated under reduced pressure. To the obtained solid, 100 ml of dry benzene was added and suspended. The produced salt was filtered through a glass filter under a nitrogen stream, and the obtained filtrate was concentrated under reduced pressure. The obtained solid was recrystallized from acetonitrile to obtain 4.96 g of white crystals of chlorocyclopentadienylbis (2,2,6,6-tetramethyl-3,5-heptanedionato) -zirconium (IV). (Yield; 66.1%).

[Overlap] 50% of internal volume fully replaced with nitrogen
Purified toluene 2 in a 0 ml glass flask
00 ml was added, and the mixture was kept at 60 ° C. for 10 minutes while flowing ethylene at 100 liter / hr.

Then, 54.0 mg of methylaluminoxane (methylaluminoxane manufactured by Schering Co., Ltd., dried and re-dissolved in toluene) was charged in terms of aluminum atom. Further, the zirconium complex was charged in an amount of 1.824 mg of zirconium atom. After conducting the polymerization at 60 ° C. for 30 minutes, the polymerization was stopped by adding a small amount of methanol.

A small amount of dilute hydrochloric acid was added to the obtained polymer suspension, which was filtered through a glass filter to remove toluene as a solvent, washed with n-hexane, and dried under reduced pressure for 24 hours. The polyethylene obtained was 0.29 g, the polymerization activity was 30 g / mmol-Zr / hr, and the intrinsic viscosity [η] was 3.97.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a process for preparing an olefin polymerization catalyst according to the present invention.

Continued Front Page (72) Inventor Shuji Minami 580-32, Takuji Nagaura, Sodegaura City, Chiba Prefecture 32 Mitsui Petrochemical Industry Co., Ltd.

Claims (4)

[Claims] 1. A transition metal compound represented by the following general formula [I] and CpM (R ¹ COCR ² COR ³ ) ₂ X ... [I] (wherein M is zirconium or hafnium). C
p is a group having a cyclopentadienyl skeleton and may have a substituent. R ¹ , R ² and R ³ have 1 carbon atom
An alkyl group having 10 to 10 carbon atoms, an alkyl group having 1 to 10 carbon atoms substituted with a halogen atom, an aryl group, an aryl group substituted with a halogen atom or an alkyl group, or a furyl group, and R ¹ and R ² are bonded to each other. And may form a ring. X is a halogen atom or -SO ₃ CF ₃
Is. And (B) an organoaluminum oxy compound. 2. The catalyst for olefin polymerization according to claim 1, wherein the transition metal compound is a compound represented by the following general formula [II]. CpZr (R ¹ COCR ² COR ³ ) ₂ Cl ... [II] (In the formula, Cp is a group having a cyclopentadienyl skeleton and may have a substituent. R ¹ , R ² and R ³
Is an alkyl group having 1 to 6 carbon atoms, an aryl group, an alkyl group substituted with a halogen atom, or a furyl group,
R ¹ and R ² may combine with each other to form a ring. ) 3. The catalyst for olefin polymerization according to claim 1, wherein the transition metal compound is chlorocyclopentadienylbis (2,4-pentadionato) zirconium. 4. A method for polymerizing an olefin, which comprises polymerizing an olefin in the presence of the catalyst according to any one of claims 1 to 3.