JP3025350B2 - Catalyst for producing syndiotactic poly-α-olefin and method for producing syndiotactic poly-α-olefin - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a process for producing syndiotactic poly-α-olefins. More specifically, the present invention relates to a method for producing a syndiotactic poly-α-olefin with high activity using a small amount of aluminoxane. More specifically, the present invention relates to a method for producing a syndiotactic poly-α-olefin with high activity using a specific transition metal compound and using a small amount of aluminoxane.

[0002]

2. Description of the Related Art Transition metal compounds having cyclopentadienyl group, indenyl group, fluorenyl group, or derivatives thereof as ligands, so-called metallocene compounds, are used together with a cocatalyst such as aluminoxane to polymerize an α-olefin. It is known that by doing so, a poly-α-olefin can be produced.

JP-A-58-19309 discloses that (cyclopentadienyl) ₂ MeRHal (where R is cyclopentadienyl, C ₁ -C ₆ alkyl and halogen, and Me is a transition metal. Yes, Ha
wherein l is a halogen), and a method of polymerizing or copolymerizing ethylene and / or an α-olefin in the presence of a catalyst comprising a transition metal compound represented by the formula: JP-A-60-35008 describes that a poly-α-olefin having a wide molecular weight distribution can be produced by using a catalyst comprising at least two kinds of metallocene compounds and an aluminoxane. JP-A-61-130314 describes a method for producing a polyolefin using a catalyst comprising a sterically fixed zircon chelate compound and an aluminoxane. The publication also discloses a method for producing a polyolefin having a high isotacticity by using ethylene-bis- (4,5,6,7-tetrahydro-1-indenyl) zirconium dichloride as a transition metal compound. Has been described. JP-A-64-66
No. 124 discloses a transition metal compound having a cyclopentadienyl compound cross-linked with silicon as a ligand and a catalyst for producing a stereoregular olefin polymer containing aluminoxane as an active ingredient.

Japanese Patent Application Laid-Open No. 2-41303 discloses that the following formula R ″ (CpR _n ) (CpR ′ _m ) MeQ _k (where each Cp is a cyclopentadienyl or substituted cyclopentadienyl ring) Each R _n can be the same or different and is a hydrocarbyl residue having 1-20 carbon atoms; each R ′ _{m can be the} same or different and a hydrocarbyl residue having 1-20 carbon atoms; R ″ is a structural bridge between Cp rings that provides steric stiffness to the catalyst; Me is 4b, 5 of the Periodic Table of the Elements.
b is a metal of group b or 6b; each Q is a hydrocarbyl residue having 1 to 20 carbon atoms or halogen;
k ≦ 3: 0 ≦ n ≦ 4 and 1 ≦ m ≦ 4; and R ′
_m is (CpR _'m) is (CpR _n) and sterically different and is selected as the metallocene catalyst used to produce the syndiotactic polyolefin is denoted by. It is described that a poly-α-olefin having good syndiotacticity can be produced by using a catalyst containing as one component. Further, the publication describes that a syndiotactic poly-α-olefin having a wide molecular weight distribution can be produced by using two or more of the above metallocene compounds.
JP-A-2-274703 discloses a compound represented by the following formula:

[0005]

Embedded image [Wherein, M ¹ is titanium, zirconium, vanadium, niobium or tantalum, and R ¹ and R ² may be the same or different from each other, and include a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, 1 carbon atom
Alkoxy group having 10 to 10 carbon atoms, aryl group having 6 to 20 carbon atoms, aryloxy group having 6 to 20 carbon atoms, alkenyl group having 2 to 10 carbon atoms, arylalkyl group having 7 to 40 carbon atoms, carbon atom Means an alkylaryl group having 7 to 40 atoms or an arylalkenyl group having 8 to 40 carbon atoms, R ³ and R ⁴ are different, and a central atom M
¹ and mononuclear capable of forming a sandwich structure together - means or polynuclear hydrocarbon radical, R ⁵ is the following formula (Formula 4)

[0006]

Embedded image= BR⁶, = AlR⁶, -Ge-, -Sn-, -O-,
-S-, = SO, = SO, = NR⁶, = CO, = PR⁶
Or = P (O) R⁶, Where R⁶, R ⁷And
And R⁸May be the same or different, and
, A halogen atom, an alkyl group having 1 to 10 carbon atoms,
Fluoroalkyl group having 1 to 10 carbon atoms, number of carbon atoms
6 to 10 fluoroaryl groups, 6 to 20 carbon atoms
Aryl group, alkoxy group having 1 to 10 carbon atoms, carbon
An alkenyl group having 2 to 10 atoms and 7 to 40 carbon atoms
Arylalkyl group, aryla having 8 to 40 carbon atoms
Lucenyl group or alkyl aryl having 7 to 40 carbon atoms
Or R⁶And R⁷Or R⁶You
And R⁸Are each formed with their attached atoms
To form a ring, and M^TwoIs silicon, germanium or
Is tin. The transition metal component represented by
Polymerization of olefins in the presence of a catalyst consisting of
And high molecular weight syndiotactic polyolefin
Are described.

JP-A-2-274704 describes a method for producing a high-molecular-weight syndiotactic polyolefin using a similar hafnium compound.
However, in a catalyst system using these aluminoxanes, it was necessary to use a large amount of expensive aluminoxanes in order to exhibit high catalytic activity. On the other hand, the active species of the above-mentioned Kaminsky type catalyst is [Cp ' ₂
MR] ⁺ (where Cp ′ = cyclopentadienyl derivative, M = Ti, Zr, Hf, R = alkyl)
Some catalyst systems that do not use aluminoxanes as cocatalysts have also been reported. Taube et al., J. Organometall. Chem.,
347 , C9 (1988) [Cp ₂ TiMe (THF)]
⁺ [BPh ₄ ] ⁻ (Me = methyl group, Ph = phenyl group) The ethylene polymerization has been successfully performed using a compound represented by the formula: Jordan et al., J. Am. Chem. Soc., 109 , 4111 (19
87) shows that zirconium complexes such as [Cp ₂ ZrR (L)] ⁺ (R = methyl group, benzyl group, L = Lewis base) polymerize ethylene.

Japanese Patent Publication No. 1-501950, Japanese Patent Publication No.
JP-A-502036 describes a method of polymerizing an olefin using a catalyst comprising a cyclopentadienyl metal compound and an ionic compound capable of stabilizing a cyclopentadienyl metal cation. Zambel
Li et al. reported in Macromolecules, 22 , 2186 (1989) that isotactic polypropylene can be produced using a catalyst combining a zirconium compound with a cyclopentadiene derivative as a ligand and trimethylaluminum and fluorodimethylaluminum. are doing. Attempts have also been made to use organic aluminum compounds in combination to reduce the amount of aluminoxane used. JP-A-2-22307 discloses a method of polymerizing an olefin using a catalyst comprising a specific hafnium compound, an aluminoxane, and an organoaluminum compound. However, the publication discloses only a hafnium compound having a ligand in which an indenyl group or a derivative thereof is bonded via a lower alkylene group as a hafnium compound, and syndiotactic poly-α as in the present invention. -No description is given of transition metal compounds having a substituted fluorenyl group as a ligand for producing olefins.

[0009]

As described above, the so-called Kaminsky catalyst system requires a large amount of expensive aluminoxane, so that the amount of aluminoxane used can be reduced,
Several catalyst systems that do not use aluminoxanes have been proposed. In a system using an ionic compound as a co-catalyst without using aluminoxane, there is a problem that an ionic compound which is difficult to synthesize must be used in order to obtain low polymerization activity or high activity. In addition, Japanese Patent Application Laid-Open No.
As described in US Pat. No. 2307, a method of reducing the amount of aluminoxane used in producing an isotactic poly-α-olefin has been found, but syndiotactic poly-α-olefin is used. There is no known method of manufacturing.

[0010]

Means for Solving the Problems The present inventors have solved the above-mentioned problems, and as a result of intensive studies on a method for producing a syndiotactic poly-α-olefin with high activity even when the amount of aluminoxane used is reduced, It has been found that the above object is achieved by using a catalyst comprising (A) a specific transition metal compound (B), an aluminoxane (C) and an organoaluminum compound, and have completed the present invention.

That is, the present invention relates to (A) a compound represented by the following general formula (I):

[0012]

Embedded image (Here, A ¹ represents a cyclopentadienyl group, a 1 to 4 substituted cyclopentadienyl group, A ² represents a 0 to 4 substituted fluorenyl group. A ³ and A ⁴ represent an alkyl group having 1 to 10 carbon atoms, And represents an aryl group, an alkylaryl group, an arylalkyl group, a halogenated aryl group or a hydrogen atom having 6 to 20 carbon atoms, wherein at least one of A ³ and A ⁴ is an aryl group, an alkylaryl group or a halogenated aryl Q is a group containing carbon, silicon, germanium or tin connecting A ¹ and A ² , and A ³ and A
⁴ may be mutually bonded to form a ring structure among A ³ , A ⁴ and Q. R ¹ and R ^{2 each} represent a halogen atom, a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, and 6 to ² carbon atoms.
It represents up to 0 aryl, alkylaryl, and arylalkyl groups. M is titanium, zirconium, hafnium. (B) a ratio of Al / M to the above transition metal compound.
An aluminoxane having a ratio of 0.01 to 1000 mole times,
And (C) triethylaluminum and triisobutylal
Transitional gold with organoaluminum compound selected from minium
Provided is a catalyst for producing a syndiotactic poly-α-olefin comprising 1 to 500 mol per 1 mol of the genus compound ,
Furthermore, the present invention is a method for producing a syndiotactic poly-α-olefin by polymerizing an α-olefin in the presence of the above catalyst.

In the general formula (I) of the transition metal compound used in the present invention, A ¹ is a cyclopentadienyl group, 1
Represents a 4-substituted cyclopentadienyl group. Specific examples of A ¹ include a cyclopentadienyl group, a methylcyclopentadienyl group, and a tetramethylcyclopentadienyl group. A ² represents a 0 to 4 substituted fluorenyl group, specifically, for example, a fluorenyl group, 1-
Examples include a methylfluorenyl group and a 2,7-di-tert-butylfluorenyl group. A ³ and A ⁴ are an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms, an alkylaryl group, an arylalkyl group, a halogenated aryl group or a hydrogen atom, and at least one of A ³ and A ⁴ One is an aryl group, an alkylaryl group or a halogenated aryl group. Specific examples of A ³ and A ⁴ include a hydrogen atom, a methyl group, an ethyl group, a propyl group, a phenyl group, a toluyl group, a fluorophenyl group, a methoxyphenyl group,
A benzyl group and the like can be mentioned. Q is A ¹ , A ²
Is a group containing carbon or silicon, germanium, or tin, and is preferably a carbon atom or a silicon atom. Also,
A ³ and A ⁴ may be bonded to each other to form a ring structure among A ³ , A ⁴ and Q. R ¹ and R ² are a halogen atom, a hydrogen atom, an alkyl group having 1 to 10 carbon atoms,
And 20 to 20 aryl groups, alkylaryl groups, and arylalkyl groups, preferably a chlorine atom, a methyl group, or a benzyl group. M represents titanium, zirconium or hafnium, preferably zirconium or hafnium.

Specific examples of the transition metal compound represented by the general formula (I) include, in addition to the transition metal compounds described in JP-A-2-274703 and JP-A-2-274704, for example, Methyl (4-fluorophenyl) methylenecyclopentadienylfluorenylzirconium dichloride, methyl (4-fluorophenyl) methylenecyclopentadienyl (2,7-di-tert-butyl-
9-fluorenyl) zirconium dichloride, bis (4
-Fluorophenyl) methylenecyclopentadienylfluorenylzirconium dichloride, bis (4-fluorophenyl) methylenecyclopentadienyl (2,7-
Other similar hafnium compounds can be mentioned in addition to di-t-butyl-9-fluorenyl) zirconium dichloride.

The transition metal compound represented by the general formula (I) is described, for example, in JP-A-2-274703 and JP-A-2-274703.
The compound can be synthesized using a method similar to a known method for synthesizing a transition metal compound as described in 274704. The aluminoxane used as the component (B) in the present invention has the following general formula (Formula 6)

[0016]

Embedded image (Where R represents a hydrocarbon group having 1 to 10 carbon atoms, and n represents an integer of 2 or more), and aluminoxane wherein R is a methyl group or an isobutyl group is preferably used. The above-mentioned aluminoxanes may contain some alkylaluminum compounds.

The method for producing the above aluminoxanes is generally as follows: (1) In a medium such as benzene, toluene, diethyl ether or tetrahydrofuran, copper sulfate hydrate, aluminum sulfate hydrate, magnesium chloride hydrate or the like is used. Method of reacting salts containing water of crystallization with trialkylaluminum (2) A method of directly reacting trialkylaluminum with water in a medium such as benzene, toluene, diethyl ether or tetrahydrofuran is used.

The ratio of the aluminoxane to the transition metal compound used as the component (A) is 0.01 to 1000 mole times, preferably 0.1 to 500 mole times as aluminum atom.

In the present invention, the organoaluminum compound used as the component (C) is represented by the general formula AlR ₃ (R is an alkyl group having 1 to 20 carbon atoms, an aryl group, an alkylaryl group, an arylalkyl group). ). Specific examples include trimethylaluminum, triethylaluminum, triisobutylaluminum, tri-n-octylaluminum, and triphenylaluminum. Preferably,
Triethyl aluminum and triisobutyl aluminum. The use ratio of the organoaluminum compound to the transition metal compound of the component (A) is 0.1 to 10
The molar ratio is 00 molar times, preferably 1 to 500 molar times. The catalyst for syndiotactic poly-α-olefin production in the present invention may be SiO ₂ , Al ₂ O ₃ , Mg
It may be used by being supported on a known carrier supporting a Ziegler-type catalyst such as Cl ₂ . The polymerization method and polymerization conditions carried out by the method of the present invention are not particularly limited, and known methods carried out in the polymerization of α-olefin are used, and a solvent polymerization method using an inert hydrocarbon medium, or a substantially inert carbon method is used. A bulk polymerization method or a gas phase polymerization method without a hydride medium can also be used, and the polymerization is generally performed at a polymerization temperature of -100 to 200 ° C and a polymerization pressure of normal pressure to 100 kg / cm ² . Preferably -50 to 100 ° C, normal pressure to 50
kg / cm ² .

The hydrocarbon medium used in the treatment or polymerization of the catalyst component in the present invention includes, for example, saturated hydrocarbons such as butane, pentane, hexane, heptane, octane, nonane, decane, cyclopentane and cyclohexane, as well as benzene. And aromatic hydrocarbons such as toluene and xylene. As the α-olefin used in the polymerization, propylene, 1-
Butene, 4-methyl-1-pentene, 1-hexene, 1
Examples thereof include α-olefins having 3 to 25 carbon atoms, such as -octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, and 1-octadecene.

In the present invention, not only homopolymerization of α-olefin but also propylene and ethylene, propylene and 1-
Ethylene having about 2 to 25 carbon atoms such as butene or α-
It can also be used when producing olefin copolymers.

[0022]

The present invention will be specifically described below with reference to examples. Example 1 A 1.5-liter autoclave sufficiently purged with nitrogen was charged with 0.75 l of propylene.
Diphenylmethylenecyclopentadienylfluorenylzirconium dichloride 2 × 10 ^-3 mmol, 5.3 mg of methylaluminoxane (degree of polymerization 17.7) manufactured by Tosoh Akzo Co., Ltd. and triisobutylaluminum 72 5 ml of a toluene solution containing 0.5 mg was pressurized with nitrogen. The polymerization temperature is 40 ° C,
Polymerization was performed for 1 hour. The polymerization was stopped by introducing a small amount of methanol into the system, unreacted propylene was purged, and dried to obtain 56.1 g of syndiotactic polypropylene powder. 135 of powder
The intrinsic viscosity (hereinafter abbreviated as [η]) measured with a tetralin solution at 4 ° C. is 4.67 dl / g, and the molecular weight dispersity (Mw / Mn) measured by GPC (gel permeation chromatography) is 2.3. Met. ^The syndiotactic pentad fraction determined from the peak intensity attributable to the methyl group of about 20.2 ppm by ¹³ C-NMR measurement was 0.90.
It was 3. Reference Example 1 Methylaluminoxane was replaced with 5.3 mg of methylaluminum
Using 150 mg of noxane to remove all alkyl aluminum
Except that it was not used well.
, 48g of syndiotactic polypropylene powder
I got it. [Η] of the powder is 4.66 dl / g,
The geotactic pentad fraction was 0.906.

Comparative Example 1 Propylene polymerization was carried out in the same manner as in Example 1 except that isopropylidenecyclopentadienylfluorenylzirconium dichloride synthesized by the method described in JP-A-2-41303 was used as a transition metal catalyst component. went. The amount of the obtained syndiotactic polypropylene powder was 2.0 g.

As described above, even when the same transition metal catalyst component that gives the same syndiotactic poly-α-olefin is used, the syndiotactic poly-α-olefin can be highly active with a small amount of aluminoxane used as in the present invention. Could not get.

Example 2 [Polymerization] of Example 1 except that 41.9 mg of triethylaluminum was used as the organoaluminum compound component.
Propylene polymerization was carried out in the same manner as described above. The resulting syndiotactic polypropylene powder was 3
8.6 g, [η] of the powder was 4.58 dl / g, Mw
/ Mn was 2.4 and the syndiotactic pentad fraction was 0.901.

Comparative Example 2 Propylene polymerization was carried out in the same manner as in [Polymerization] of Example 1 without using methylaluminoxane, but no syndiotactic polypropylene could be obtained.

[0027]

Industrial Applicability By using the catalyst of the present invention and carrying out the method of the present invention, a highly active syndiotactic poly-α-olefin can be produced with a small amount of aluminoxane to be used industrially. Extremely valuable.

────────────────────────────────────────────────── ─── Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) C08F 4/60-4/70

Claims (2)

(57) [Claims] (A) General formula (I) (Chemical formula 1) (Here, A ¹ represents a cyclopentadienyl group, a 1 to 4 substituted cyclopentadienyl group, A ² represents a 0 to 4 substituted fluorenyl group. A ³ and A ⁴ represent an alkyl group having 1 to 10 carbon atoms, And represents an aryl group, an alkylaryl group, an arylalkyl group, a halogenated aryl group, or a hydrogen atom having 6 to 20 carbon atoms, and at least one of A ³ and A ⁴ is an aryl group, an alkylaryl group, or a halogenated aryl group. Q is a carbon or a group containing silicon, germanium or tin connecting A ¹ and A ² , and A ³ and A
⁴ may be mutually bonded to form a ring structure among A ³ , A ⁴ and Q. R ¹ and R ^{2 each} represent a halogen atom, a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms, an alkylaryl group, or an arylalkyl group. M is titanium, zirconium, hafnium. (B) a ratio of Al / M to the above transition metal compound.
An aluminoxane having a ratio of 0.01 to 1000 mole times,
And (C) triethylaluminum and triisobutylal
Transitional gold with organoaluminum compound selected from minium
A catalyst for syndiotactic poly-α-olefin production comprising 1 to 500 mol per 1 mol of the genus compound . 2. A method for producing a syndiotactic poly-α-olefin by polymerizing an α-olefin, wherein (A) a compound represented by the following general formula (I): (Here, A ¹ represents a cyclopentadienyl group, a 1 to 4 substituted cyclopentadienyl group, A ² represents a 0 to 4 substituted fluorenyl group. A ³ and A ⁴ represent an alkyl group having 1 to 10 carbon atoms, And represents an aryl group, an alkylaryl group, an arylalkyl group, a halogenated aryl group, or a hydrogen atom having 6 to 20 carbon atoms, and at least one of A ³ and A ⁴ is an aryl group, an alkylaryl group, or a halogenated aryl group. Q is a carbon or a group containing silicon, germanium or tin connecting A ¹ and A ² , and A ³ and A
⁴ may be mutually bonded to form a ring structure among A ³ , A ⁴ and Q. R ¹ and R ^{2 each} represent a halogen atom, a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms, an alkylaryl group, or an arylalkyl group. M is titanium, zirconium, hafnium. (B) a ratio of Al / M to the above transition metal compound.
An aluminoxane having a ratio of 0.01 to 1000 mole times,
And (C) triethylaluminum and triisobutylal
Transitional gold with organoaluminum compound selected from minium
A method for producing a syndiotactic poly-α-olefin, comprising using a catalyst comprising 1 to 500 mol per 1 mol of a genus compound .