JP3350561B2 - Transition metal catalyst component for olefin polymerization - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a transition metal catalyst component for olefin polymerization. Specifically, the present invention relates to a novel transition metal catalyst component for olefin polymerization having a cyclopentadienyl ligand and a diene ligand, which is used in combination with an aluminoxane or the like.

[0002]

2. Description of the Related Art Conventionally, in producing an olefin polymer by polymerizing an olefin in the presence of a catalyst, a transition metal compound of Group IVB of the periodic table having two cyclopentadienyl ligands as a catalyst has been used. The method using an aluminoxane is widely known. However,
As for Ta and Nb of the VB group, no catalyst system having remarkable olefin polymerization ability was known.

[0003]

The object of the present invention is to provide a Ta or Nb complex having a novel ligand as an olefin polymerization catalyst component.

[0004]

Means for Solving the Problems The present inventors have intensively searched for a novel catalyst system in order to provide an olefin polymerization method which can replace the above-mentioned prior art, and as a result, have reached the present invention. That is, the present invention has a general formula

[0005]

Embedded image (CpR ′ ₅ ) M (diene) X ₂

Wherein CpR ′ ₅ represents a substituted or unsubstituted cyclopentadienyl group, and R ′ may be the same or different, hydrogen, a hydrocarbon group having 1 to 20 carbon atoms, and 2 carbon atoms; A hydrocarbon group or a silyl group whose atoms may be bonded to two carbon atoms of a cyclopentadienyl group to form a C _{4 to} C ₆ ring. M is Ta or Nb. diene is a general formula

[0007]

Embedded image

(R ^{1 to} R ⁶ may be the same or different and may be hydrogen, an alkyl group or an aryl group having 1 to 4 carbon atoms). X is the same or different and is hydrogen, halogen or a hydrocarbon group having 1 to 20 carbon atoms. ] The transition metal catalyst component for olefin polymerization represented by these.

Hereinafter, the present invention will be described in detail. The transition metal compound of the present invention is used for the polymerization of olefins in combination with a cocatalyst such as an organoaluminum compound such as aluminoxane or an ionic compound. The transition metal compound of the present invention has the general formula

[0010]

[Of 5] _{(CpR '5) M (diene} ) X 2

A new transition metal compound having a cyclopentadienyl ligand and a diene ligand represented by the following formula: The general formula CpR _'5 represents a substituted or unsubstituted cyclopentadienyl group. R ′ may be the same or different and is hydrogen, a hydrocarbon group having 1 to 20 carbon atoms, or a silyl group.

Examples of the hydrocarbon group include alkyl, aryl, alkenyl, alkylaryl, arylalkyl and the like, preferably alkyl, particularly preferably methyl. Examples of the cyclopentadienyl group having hydrogen and / or a methyl group as a substituent include a cyclopentadienyl group and a pentamethylcyclopentadienyl group, with a pentamethylcyclopentadienyl group being preferred.

As the hydrocarbon group, a hydrocarbon group in which two carbon atoms are bonded to two carbon atoms of a cyclopentadienyl group to form a C ₄ -C ₆ ring is also used, and an indenyl group, a tetrahydro group And an indenyl group and a fluorenyl group. Examples of the silyl group include a trimethylsilyl group and a triethylsilyl group. M is Ta or Nb. Particularly, Ta is preferable. diene is a general formula

[0014]

Embedded image

(R ^{1 to} R ⁶ may be the same or different and may be hydrogen, an alkyl group having 1 to 4 carbon atoms or an aryl group). Examples of the alkyl group having 1 to 4 carbon atoms include methyl, ethyl, propyl, and butyl. Specific compounds include butadiene, isoprene, 2,3-dimethylbutadiene, and 1,4-diphenyl-1,3-butadiene, 1,3
-Pentadiene and the like. X may be the same or different, and may be hydrogen, halogen, having 1 to 2 carbon atoms.
Represents a hydrocarbon group of 0, and examples of the halogen include chlorine, bromine, iodine, and fluorine, and chlorine is particularly preferable. Examples of the hydrocarbon group having 1 to 20 carbon atoms include alkyl, aryl, alkenyl, alkylaryl, and arylalkyl. Usually, methyl and phenyl are used. Specific examples of the above transition metal compounds include (pentamethylcyclopentadienyl-isoprene) tantalum dichloride, (pentamethylcyclopentadienyl-butadiene) tantalum dichloride, and (cyclopentadienyl-butadiene) tantalum dichloride. ,
(Pentamethylcyclopentadienyl-isoprene) tantalum dimethyl, (pentamethylcyclopentadienyl-isoprene) tantalum diphenyl, (cyclopentadienyl-isoprene) tantalum dimethyl, (pentamethylcyclopentadienyl-2,3-dimethyl) -1,3-
(Butadiene) tantalum dimethyl, (pentamethylcyclopentadienyl-butadiene) tantalum dimethyl, (pentamethylcyclopentadienyl-1,4-diphenyl-1,3-butadiene) tantalum dimethyl, (pentamethylcyclopentadienyl-1) , 3-pentadiene) tantalum dimethyl, (pentamethylcyclopentadienyl-isoprene) niobium dimethyl, and the like.

As a method for synthesizing the transition metal compound of the present invention,
Is, for example, CpM (diene) X _Two(X = halogen
The compound represented by (C) is CpMX_FourRepresented by
2 equivalents of allyl Grignard to clopentadienyl chloride
It is obtained by reacting a compound. X is al
In the case of a kill group, for example, the CpM (d
ie) X_TwoAlkyl Grignard compounds in addition to compounds
Is obtained by reacting For olefin polymerization
Alumino combined with the transition metal catalyst component of the present invention
The general formula for xane

[0017]

Embedded image

[0018]

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An organoaluminum compound represented by the following formula is used. R ⁷ is a hydrocarbon group having 1 to 20 carbon atoms, and is preferably a methyl group. m is an integer of 4 to 30, and particularly preferably 10 or more. Aluminoxane manufactured by a known method may be used. Examples of the organoaluminum other than aluminoxane include trialkylaluminums such as trimethylaluminum and triethylaluminum. The use ratio of the transition metal catalyst component for olefin polymerization of the present invention and the organoaluminum is expressed by the ratio of transition metal in the former to Al in the organoaluminum: 1:
It is selected to be 1 to 100,000, preferably 10 to 2,000. The present invention is characterized in that a desired performance can be obtained by using a small amount of an organoaluminum compound with respect to the transition metal catalyst component.

The transition metal catalyst component for olefin polymerization of the present invention can be used in combination with an ionized compound. Such compounds include, for example, triphenylcarbenium tetrakis (pentafluorophenyl) borate, N, N-dimethylanilinium tetrakis (pentafluorophenyl) borate, tris (pentafluorophenyl) boron and the like. The ratio of the transition metal catalyst component for olefin polymerization of the present invention to the ionized compound is 0.5: 1 to 5: 1 in terms of the ratio of transition metal to B in the ionized compound in the former. As the olefin, ethylene, propylene, 1-butene, 1-hexene, 3-methylbutene-1, 4-methylpentene-1, styrene and the like are used. These olefins can be copolymerized. The polymerization reaction is butane, pentane, hexane,
Aliphatic hydrocarbons such as heptane, alicyclic hydrocarbons such as cyclohexane, aromatic hydrocarbons such as toluene and xylene,
Alternatively, the reaction is performed in the presence or absence of a solvent such as a halogenated hydrocarbon such as methylene chloride. The temperature is
The temperature is −50 to 250 ° C., and the pressure is not particularly limited. Further, hydrogen may be present as a molecular weight regulator in the polymerization system.

[0021]

Next, the present invention will be described in more detail with reference to Examples.
However, the present invention does not depart from the gist of the present invention.
However, the present invention is not limited by the embodiments. Also figure
1 is a file for helping to understand the technical contents included in the present invention.
FIG. 5 is a flowchart, and the present invention does not depart from the gist thereof
As far as this flowchart is concerned,
Not. Example 1 (1) Synthesis of transition metal catalyst component^*Is pentamethylcyclopentadie
Represents a nyl group. Cp^*K and SiMe_ThreeCl (Me is
SiMe obtained by the reaction with _ThreeCp^*To
Further TaCl_FiveAnd react with Cp^*TaCl_FourSynthesize
did. Then this Cp^*TaCl_Four(1.36g,
2.97 mmol) in 20 ml of THF
Cool. This solution was dissolved in 12 ml of ether (i
sopreny) MgCl 6 mmol was added dropwise. This
Solution until it returns to room temperature.
I left. Recrystallization from a mixed solvent of hexane and toluene
No, 0.97g Cp^*TaCl_Two(Isopren
e) was obtained (yield 72%). This complex (0.29 g,
0.65 mmol) in THF (30 ml).
After cooling to 40 ° C., MeMgI (f = 0.98, 1.3 m
1, THF) was added dropwise. Return to room temperature after completion of dropping
The product is extracted with hexane and recrystallized from hexane.
Dark purple needle-shaped crystal Cp^*TaMe_Two(Isopr
ene) in 50% yield. Its melting point is 91
° C. (2) Polymerization of ethylene Cp obtained above^*TaMe_Two(Isoprene)
11 mg (0.027 mmol) of the complex was dissolved in toluene (15
ml), and add -600 eq.
Chill aluminoxane (Tosoh Akzo, MW = 1
100) was added to prepare a catalyst. Purple at -78 ° C
The color of the solution turned light yellow while returning to room temperature. This
The solution was stirred at 20 ° C for 6 hours in the presence of 1 atm of ethylene.
Done. After removing the gas, add methanol.
And 0.26 g of polyethylene was obtained.
From this result, a polymerization activity of 1.6 kgPE / hr · m
ol values were obtained. The molecular weight of the obtained polyethylene is poly
2.030,000 in terms of styrene and Mw / Mn = 1.7
there were.

Example 2 (Ethylene polymerization) In Example 1, the amount of methylaluminoxane was changed to 50, 100, 200, 400, 100
The polymerization was carried out in the same manner as in Example 1 except that the equivalent was 0 equivalent, and the polymerization activities were 0.7, 0.8, 1.0, 1.8,
A value of 1.6 kgPE / hr-mol was obtained.

Example 3 (Polymerization of ethylene) Cp ^* T was prepared in the same manner as in Example 1.
aCl ₂ (isoprene) (12 mg, 0.026
6 mmol) was dissolved in 20 ml of toluene, and 900 equivalents of methylaluminoxane were added. Stirring was performed at 20 ° C. for 6 hours in the presence of 1 atm of ethylene. After terminating the reaction with methanol, the polymer was vacuum dried. 0.21 g of polyethylene was obtained. The polymerization activity is 1.3 kg / hr ·
mol

Example-4 Cp ^* TaCl ₂ (buta ^{) was} obtained in the same manner as in Example-1.
diene) (11.6 mg, 0.0266 mmol)
Was dissolved in 20 ml of toluene, and 500 equivalents of methylaluminoxane were added. Stirring was performed at 20 ° C. for 6 hours in the presence of 1 atm of ethylene. After terminating the reaction with methanol, the polymer was dried under vacuum. 0.95 g of polyethylene was obtained. The polymerization activity was 5.9 kg PE / hr · mol.

Example-5 Cp ^* TaMe ₂ (buta ^{) was} obtained in the same manner as in Example-1.
diene) (10.5 mg, 0.0266 mmol)
Was dissolved in 20 ml of toluene, and 500 equivalents of methylaluminoxane were added. Stirring was performed at 20 ° C. for 6 hours in the presence of 1 atm of ethylene. After terminating the reaction with methanol, the polymer was dried under vacuum. 0.71 g of polyethylene was obtained. The polymerization activity was 4.5 kgPE / hr · mol.

Comparative Example 1 (1) Synthesis of Transition Metal Catalyst Component Cp ₂ NbCl ₂ (Cp is a cyclopentadienyl group) was synthesized by a method described in the literature. Reference: F. W. Siegert, H .; J. de Lie
fde MeijerJ. Organometalli
c Chemistry, 23 , 177 (1970) (2) Polymerization of ethylene Methylaluminoxane was added to Cp ₂ NbCl ₂ in toluene so that the molar ratio of Al / Nb became 10, 20, and 50 to prepare a catalyst. In the presence of these catalysts,
At room temperature, 1 atmosphere of ethylene was reacted for 6 hours. After the reaction, methanol was added, but no precipitation of polyethylene was observed.

[0027]

The olefin polymer can be obtained efficiently by using the Ta or Nb compound having the cyclopentadienyl ligand and the diene ligand of the present invention as the transition metal catalyst component for olefin polymerization. . In contrast, N having two cyclopentadienyl ligands
A catalyst system comprising a complex of b and Ta and an aluminoxane is not suitable for an olefin polymerization catalyst.

[Brief description of the drawings]

FIG. 1 is a flowchart illustrating one embodiment of the present invention.

Continuation of front page (56) References Am. Chem. Soc. 1987, Vol. 109, No. 21, pp. 6506-6508. Organomet. Chem. April 28, 1992, Vol. 428 No. 1-2, C5-C7 Organometallics, 1989, Vol. 8, No. 7, pp. 1644-1651, Organometallics, 1995, Vol. 14, pp. 2633-2640 ( 58) Field surveyed (Int.Cl. ⁷ , DB name) C08F 4/60-4/70 CA (STN) REGISTRY (STN)

Claims (1)

(57) [Claims] 1. A compound represented by the general formula: (CpR ′ ₅ ) M (diene) X ₂ [where CpR ′ ₅ represents a substituted or unsubstituted cyclopentadienyl group, and R ′ may be the same or different. Good hydrogen, a hydrocarbon group having 1 to 20 carbon atoms, and a hydrocarbon wherein two carbon atoms may be respectively bonded to two carbon atoms of a cyclopentadienyl group to form a C ₄ -C ₆ ring Or a silyl group. M is Ta or Nb. diene has the general formula (R ^{1 to} R ⁶ may be the same or different and may be hydrogen, an alkyl group or an aryl group having 1 to 4 carbon atoms). Xs may be the same or different and each represents a hydrogen, a halogen, or a group having 1 carbon atom.
To 20 hydrocarbon groups. ] The transition metal catalyst component for olefin polymerization represented by these.