JPH05310828A - Transition metal catalyst component for polymerization of olefin - Google Patents

Abstract

PURPOSE:To obtain the catalyst component which can give an olefin polymer at good efficiency by incorporating a tantalum or niobium compound containing cyclopentadiene ligands and diene ligands. CONSTITUTION:The catalyst component is one resented by formula I wherein CpR'5 is (substituted) cyclopentadienyl; R' is H, a 1-20 C hydrocarbon group, a hydrocarbon group two carbon atoms of which may be bonded respectively to the two carbon atoms of the cyclopentadienyl group to form a 4-6 C ring, or silyl; M is Ta or Nb; diene is a conjugated diene compound of formula II (wherein R<1> to R<6> are each H, 1-4 C alkyl or aryl); and X is H, halogen or a 1-20C hydrocarbon group. By using this compound as a metallic catalyst component for the polymerization of an olefin, an olefin polymer can be obtained at good efficiency.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a transition metal catalyst component for olefin polymerization. More 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 aluminoxane or the like.

[0002]

2. Description of the Related Art Conventionally, for 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 is used as a catalyst. A method using an aluminoxane is widely known. However,
For Ta and Nb of Group VB, no catalyst system with a remarkable olefin polymerization ability was known.

[0003]

DISCLOSURE OF THE INVENTION The present invention is to provide a Ta or Nb complex having a novel ligand as an olefin polymerization catalyst component.

[0004]

The present inventors have arrived at the present invention as a result of earnestly searching for a new catalyst system in order to provide an olefin polymerization method which can replace the above-mentioned conventional technique. That is, the present invention has the general formula

[0005]

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

[CpR ' ₅ represents a substituted or unsubstituted cyclopentadienyl group, R'may be the same or different, hydrogen, a hydrocarbon group having 1 to 20 carbon atoms, 2 carbon atoms atoms are cyclopentadienyl two hydrocarbon group which may form a C ₄ -C ₆ ring attached respectively to a carbon atom of the group or a silyl group. M is Ta or Nb. diene is a general formula

[0007]

[Chemical 4]

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

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

[0010]

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

A novel transition metal compound having a cyclopentadienyl ligand and a diene ligand represented by: In the above general formula, CpR ′ ₅ represents a substituted or unsubstituted cyclopentadienyl group. R'may be the same or different, but 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, etc., 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, and among them, a pentamethylcyclopentadienyl group is preferable.

As the hydrocarbon group, a hydrocarbon group in which two carbon atoms are respectively 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 are used. Examples thereof include 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. Ta is particularly preferable. diene is a general formula

[0014]

[Chemical 6]

(R ^{1 to} R ⁶ are hydrogen, which may be the same or different, and are an alkyl group or an aryl group having 1 to 4 carbon atoms), which is a conjugated diene compound. 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's may be the same or different and each is hydrogen, halogen, or has 1 to 2 carbon atoms.
Representing a hydrocarbon group of 0, examples of 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, and usually methyl and phenyl are used. Specific examples of the above transition metal compounds include (pentamethylcyclopentadienyl-isoprene) tantalum dichloride, (pentamethylcyclopentadienyl-butadiene) tantalum dichloride, (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 ₂(X = haloge
Compound represented by CpMX_FourRepresented by
2 equivalents of allyl Grignard to clopentadienyl chloride
It is obtained by reacting a compound. Also, X is Al
In the case of a kill group, for example, CpM (d
iene) X₂Alkyl Grignard compound
It is obtained by reacting. During olefin polymerization
Alumino combined with the transition metal catalyst component of the present invention.
The general formula for xane

[0017]

[Chemical 7]

[0018]

[Chemical 8]

An organoaluminum compound represented by is used. R ⁷ is a hydrocarbon group having 1 to 20 carbon atoms, preferably a methyl group. m is an integer of 4 to 30, particularly preferably 10 or more. As the aluminoxane, those produced by a known method may be used. Examples of the organic aluminum other than aluminoxane include trialkylaluminums such as trimethylaluminum and triethylaluminum. The ratio of the transition metal catalyst component for olefin polymerization and the organoaluminum used in the present invention is 1: the ratio of transition metal in the former to Al in the organoaluminum.
It is selected to be 1 to 100,000, preferably 10 to 2,000. The present invention is characterized in that desired performance can be obtained by using a small amount of 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. Examples of such a compound include 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 used is 0.5: 1 to 5: 1 in terms of the ratio of B in the transition metal to the ionized compound in the former. As the olefin, ethylene, propylene, 1-butene, 1-hexene, 3-methylbutene-1,4-methylpentene-1, styrene or the like is used. It is also possible to copolymerize these olefins. 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, it is carried out in the presence or absence of a solvent such as a halogenated hydrocarbon such as methylene chloride. The temperature is
It is −50 to 250 ° C., and the pressure is not particularly limited. Further, hydrogen may be present as a molecular weight modifier in the polymerization system.

[0021]

EXAMPLES Next, the present invention will be described in more detail with reference to Examples.
However, the present invention is not limited to this without departing from the gist thereof.
No limitation is imposed by the examples. Also, the figure
1 is a function for helping understanding of the technical contents included in the present invention.
It is a chart chart, and the present invention does not deviate from the gist thereof.
As long as there is any restriction due to this flow chart
Not of. Example-1 (1) Synthesis of transition metal catalyst component Cp in the following examples^*Is pentamethylcyclopentadiene
Represents a nyl group. Cp^*K and SiMe₃Cl (Me is
SiMe obtained by reaction with ₃Cp^*To
Further TaCl_FiveReact with Cp^*TaCl_FourSynthesize
did. Next, this Cp^*TaCl_Four(1.36 g,
2.97 mmol) in 20 ml of THF,
Cooled. This solution was dissolved in 12 ml of ether (i
Soprenyl) MgCl 6 mmol was added dropwise. This
Solution until the temperature returns to room temperature, and then the solvent is distilled off under reduced pressure.
Left. Recrystallization is performed from a mixed solvent of hexane and toluene.
No, 0.97g Cp^*TaCl₂(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. After dropping, return to room temperature and generate
The product was extracted with hexane and recrystallized from hexane.
Cp which is a deep purple needle crystal^*TaMe₂(Isopr
ene) was obtained in a yield of 50%. The melting point of this product is 91
It was ℃. (2) Polymerization of ethylene Cp obtained above^*TaMe₂(Isoprene)
11 mg (0.027 mmol) of the complex was added to toluene (15
ml) and add 600 equivalents of this solution at -78 ° C.
Chill aluminoxane (Tosoh Akzo, MW = 1,
100) was added to prepare a catalyst. Purple at -78 ° C
The color of the resulting solution turned light yellow during returning to room temperature. This
The solution of was stirred for 6 hours in the presence of ethylene at 20 ° C and 1 atm.
I did. After removing the gas from the reaction, add methanol.
Then, the operation was stopped and 0.26 g of polyethylene was obtained.
From this result, the polymerization activity was 1.6 kg PE / hr · m.
The value of ol was obtained. The molecular weight of the obtained polyethylene is
2030,000 in terms of styrene, and Mw / Mn = 1.7
there were.

Example-2 (Polymerization of ethylene) In Example-1, the amount of methylaluminoxane was 50, 100, 200, 400, 100.
Polymerization was performed in the same manner as in Example 1 except that the amount was 0 equivalent, and the polymerization activity was 0.7, 0.8, 1.0, 1.8, respectively.
A value of 1.6 kg PE / 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 was added. The mixture was stirred at 20 ° C. for 6 hours in the presence of ethylene at 1 atm. After the reaction was stopped with methanol, the polymer was vacuum dried. 0.21 g of polyethylene was obtained. Polymerization activity is 1.3 kg / hr.
mol

Example 4 Cp ^* TaCl ₂ (buta ^{) was} prepared 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 was added. The mixture was stirred at 20 ° C. for 6 hours in the presence of ethylene at 1 atm. After quenching the reaction with methanol, the polymer was dried under vacuum. 0.95 g of polyethylene was obtained. The polymerization activity was 5.9 kgPE / hr · mol.

Example-5 In the same manner as in Example-1, Cp ^* TaMe ₂ (buta) was used.
diene) (10.5 mg, 0.0266 mmol)
Was dissolved in 20 ml of toluene, and 500 equivalents of methylaluminoxane was added. The mixture was stirred at 20 ° C. for 6 hours in the presence of ethylene at 1 atm. After quenching 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 cyclopentadienyl group) was synthesized by the method described in the literature. Literature: F. W. Siegert, H .; J. de Lie
fde Meijer J. Organometalli
c Chemistry, 23 , 177 (1970) (2) Polymerization of ethylene Methylaluminoxane was added to Cp ₂ NbCl ₂ in toluene so that the Al / Nb molar ratio was 10, 20, and 50 to prepare a catalyst. In the presence of these catalysts,
Ethylene at 1 atm was reacted at room temperature for 6 hours. After the reaction, methanol was added, but precipitation of polyethylene was not observed.

[0027]

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

[Brief description of drawings]

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

Claims (1)

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