JP2882257B2 - Method for producing ethylene / α-olefin copolymer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ethylene / olefin polymerization catalyst comprising a metallocene compound, an organoaluminum compound and an ionized ionic compound.
The present invention relates to a method for producing an α-olefin copolymer.

[0002]

2. Description of the Prior Art Processes for polymerizing ethylene or general α-olefins by the low-pressure Ziegler process are known in the art. Catalysts used for this purpose include transition metals mixed with organometallic compounds or hydrides of elements from Groups 1A to 3A of the Periodic Table (Groups 3B to 2B of the Periodic Table).
From a compound of the genus), operating in suspension or solution,
Alternatively, they are generally prepared by operating in the absence of a solvent or diluent.

[0003] In addition to the above-mentioned catalysts, recently, special kinds of catalysts which are active in the polymerization of olefins have been developed. As such catalysts, metals such as titanium, zirconium and hafnium (Group 4B of the periodic table) are used. A combination of a cyclopentadienyl derivative and an aluminoxane is known (for example, J. Boor, "Ziegler-Natta Catalyst and Polymerization", Academic Pre.)
ss. New York (1979) or H.E. Si
nn and W.I. Kaminsky Adv. Organ
omet. Chem. 1899 (1980)). These catalysts have the advantage of high catalytic activity and the ability to produce stereoregular olefin polymers.

[0004] However, the main reason that has hindered the industrial use of these catalysts on a large scale is that it is basically difficult to synthesize aluminoxane in a reproducible form. It is difficult to prepare the provided catalysts and polymers, and the aluminoxane is expensive, but in order to obtain a sufficient activity, the use ratio of the aluminoxane to the transition metal compound is significantly increased. It had to be higher.

In order to solve this drawback, Japanese Patent Application Laid-Open No. 3-207704 proposes using an ionic metallocene compound produced by reacting a metallocene compound with an ionized ionic compound as a catalyst. . WO 92-1723 describes a method for polymerizing an α-olefin using a catalyst system comprising reacting a halogenated metallocene compound with an organometallic compound and further contacting the reaction product with an ionized ionic compound. It is disclosed that such a catalyst system is advantageously used as an olefin polymerization catalyst. However, when ethylene and α-olefin are copolymerized at a high temperature using these catalysts, there is a problem that the resulting copolymer has a low molecular weight.

Further, Japanese Patent Application Laid-Open No. 60-217209 discloses that a high molecular weight olefin polymer can be produced by using a hafnium compound as a metallocene compound as a component of a catalyst. However, when this catalyst is used in the copolymerization of ethylene and an α-olefin, the activity is considerably inferior to that of a catalyst using a zirconium compound holding the same ligand, and there is a problem in the production efficiency of the copolymer. was there.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve this problem, and an object of the present invention is to provide a method for efficiently producing an ethylene / α-olefin copolymer at a high temperature. is there.

[0008]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have found that ethylene and α-olefin are copolymerized at a polymerization temperature of 120 ° C. or higher using a specific ionic metallocene catalyst. It has been found that an ethylene / α-olefin copolymer can be obtained with high activity by polymerization, and the present invention has been completed. That is, the present invention
An ethylene / α-olefin copolymer which copolymerizes ethylene and an α-olefin having 3 or more carbon atoms using a catalyst for olefin polymerization comprising a) a metallocene compound, b) an ionized ionic compound and c) an organoaluminum compound. In the method for producing a polymer, a) a metallocene compound represented by the following general formula (1) or (2):

[0009]

Embedded image

[0010]

Embedded image

Wherein Cp ¹ and Cp ² are each independently substituted
Or an unsubstituted cyclopentadienyl, indenyl or
Is a fluorenyl group, and R ¹ is a substituted or unsubstituted alkenyl group.
Kylene group, dialkylsilanediyl group, dialkyl gel
Mandiyl group, alkylphosphinediyl group or alk
An imino group , R ¹ acts to crosslink Cp ¹ and Cp ² , and R ² and R ³ each independently represent a hydrogen atom,
A halonium compound represented by a halogen atom, a hydrocarbon group having 1 to 12 carbon atoms, an alkoxy group or an aryloxy group), and b) a compound capable of converting the above metallocene compound into a cationic metallocene compound as an ionized ionic compound. And a compound which does not react with the formed cationic metallocene compound, and c) an organoaluminum compound represented by the following general formula (3)

[0012]

Embedded image

(Wherein R ⁴ , R ^{4 ′} and R ^{4 ″} are each independently a hydrogen atom, a halogen atom, an amino group , an alkyl group, an alkoxy group or an aryl group, and at least one is an alkyl group. Using the compound represented by
A method for producing an ethylene / α-olefin copolymer, wherein polymerization is carried out at a polymerization temperature of at least ℃.

The metallocene compound (a) used in the present invention is a hafnium compound represented by the general formula (1) or (2), and specific examples thereof include bis (cyclopentadienyl) hafnium dichloride and bis (cyclopentadienyl) hafnium dichloride. methylcyclopentadienyl) hafnium dichloride, bis (butylcyclopentadienyl) hafnium dichloride, ethylenebis (indenyl) hafnium dichloride, dimethyl silanediyl bis (2,4,5-trimethyl cyclopentadienyl) hafnium dichloride, dimethyl silanediyl bis (3-methylcyclopentadienyl) hafnium dichloride, dimethyl silanediyl <br/> bis (4-t-butyl, 2-methylcyclopentadienyl) hafnium dichloride, diethyl silanediyl bi <br/> scan (2,4 , 5-trimethyl-cyclopentadienyl) hafnium dichloride, diethyl silanediyl bis (2,4-dimethyl cyclopentadienyl) hafnium dichloride, diethyl silanediyl bis (3-methylcyclopentadienyl) hafnium dichloride, diethyl silanediyl bis (4- t-butyl, 2-methylcyclopentadienyl) hafnium dichloride, isop
Lopylidene (cyclopentadienyl) (fluorenyl)
Hafnium dichloride, diphenylmethylene (cyclopentadienyl) (fluorenyl) hafnium dichloride, methylphenylmethylene (cyclopentadienyl) (fluorenyl) hafnium dichloride, isopium
Lopylidene (cyclopentadienyl) (2,7-di - t
-Butylfluorenyl) hafnium dichloride, diphenylmethylene (cyclopentadienyl) (2,7-di
- t-butyl fluorenyl) hafnium dichloride,
Methyl phenyl methylene (cyclopentadienyl)
(2,7-di - t-butylfluorenyl) hafnium dichloride, isopropylidenebis (cyclopentadienyl) hafnium dichloride, diphenylmethylenebis (cyclopentadienyl) hafnium dichloride,
Methylphenylmethylenebis (cyclopentadienyl)
Hafnium dichloride, isopropylidene (cyclopentadienyl) (tetramethylcyclopentadienyl)
Hafnium dichloride, diphenylmethylene (cyclopentadienyl) (tetramethylcyclopentadienyl) hafnium dichloride, isopropylidenebis (indenyl) hafnium dichloride, diphenylmethylenebis (indenyl) hafnium dichloride, methylphenylmethylenebis (indenyl) hafnium dichloride, etc. But are not limited to these.

The b) ionized ionic compound used in the present invention is a compound capable of converting the above metallocene compound into a cationic metallocene compound and does not react with the formed cationic metallocene compound. Specifically, tri (n-butyl) ammonium tetrakis (p-tolyl) borate, tri (n-butyl) ammonium tetrakis (m-tolyl) borate, tri (n-butyl) ammonium tetrakis (2,
4-dimethylphenyl) borate, tri (n-butyl)
Ammonium tetrakis (3,5-dimethylphenyl)
Borate, tri (n-butyl) ammonium tetrakis (pentafluorophenyl) borate, N, N-dimethylanilinium tetrakis (p-tolyl) borate,
N, N-dimethylanilinium tetrakis (m-tolyl) borate, N, N-dimethylanilinium tetrakis (2,4-dimethylphenyl) borate, N, N-dimethylanilinium tetrakis (3,5-dimethylphenyl) borate , N, N-dimethylanilinium tetrakis (pentafluorophenyl) borate, triphenylcarbenium tetrakis (p-tolyl) borate, triphenylcarbenium tetrakis (m-tolyl) borate, triphenylcarbenium tetrakis (2,4-
Dimethylphenyl) borate, triphenylcarbeniumtetrakis (3,5-dimethylphenyl) borate,
Triphenylcarbenium tetrakis (pentafluorophenyl) borate, tropylium tetrakis (p-tolyl) borate, tropylium tetrakis (m-tolyl) borate, tropylium tetrakis (2,4-dimethylphenyl) borate, tropylium tetrakis (3 , 5-dimethylphenyl) borate, tropylium tetrakis (pentafluorophenyl) borate, lithium tetrakis (pentafluorophenyl) borate,
Lithium tetrakis (phenyl) borate, lithium tetrakis (p-tolyl) borate, lithium tetrakis (m-tolyl) borate, lithium tetrakis (2,4
-Dimethylphenyl) borate, lithium tetrakis (3,5-dimethylphenyl) borate, lithium tetrafluoroborate, sodium tetrakis (pentafluorophenyl) borate, sodium tetrakis (phenyl) borate, sodium tetrakis (p-tolyl) borate, sodium tetrakis (M-tolyl) borate, sodium tetrakis (2,4-dimethylphenyl) borate, sodium tetrakis (3,5-dimethylphenyl) borate, sodium tetrafluoroborate, potassium tetrakis (pentafluorophenyl) borate, potassium tetrakis (phenyl) Borate, potassium tetrakis (p-tolyl) borate, potassium
Um tetrakis (m-tolyl) borate, potassium tetrakis (2,4-dimethylphenyl) borate, potassium tetrakis (3,5-dimethylphenyl) borate, boron compounds such as potassium tetrafluoroborate, tri (n- butyl) ammonium tetrakis (P-
Tolyl) aluminate, tri (n-butyl) ammonium tetrakis (m-tolyl) aluminate, tri (n-
Butyl) ammonium tetrakis (2,4-dimethylphenyl) aluminate, tri (n-butyl) ammonium tetrakis (3,5-dimethylphenyl) aluminate, tri (n-butyl) ammonium tetrakis (pentafluorophenyl) aluminate, N, N-dimethylanilinium tetrakis (p-tolyl) aluminate,
N, N-dimethylanilinium tetrakis (m-tolyl) aluminate, N, N-dimethylanilinium tetrakis (2,4-dimethylphenyl) aluminate,
N, N-dimethylanilinium tetrakis (3,5-dimethylphenyl) aluminate, N, N-dimethylanilinium tetrakis (pentafluorophenyl) aluminate, triphenylcarbenium tetrakis (p-tolyl) aluminate, triphenyl Carbenium tetrakis (m-tolyl) aluminate, triphenylcarbenium tetrakis (2,4-dimethylphenyl) aluminate, triphenylcarbenium tetrakis (3,5
-Dimethylphenyl) aluminate, triphenylcarbenium tetrakis (pentafluorophenyl) aluminate, tropylium tetrakis (p-tolyl) aluminate, tropylium tetrakis (m-tolyl) aluminate, tropylium tetrakis (2,4- Dimethylphenyl) aluminate, tropylium tetrakis (3
5-dimethylphenyl) aluminate, tropylium tetrakis (pentafluorophenyl) aluminate, lithium tetrakis (pentafluorophenyl) aluminate, lithium tetrakis (phenyl) aluminate,
Lithium tetrakis (p-tolyl) aluminate, lithium tetrakis (m-tolyl) aluminate, lithium tetrakis (2,4-dimethylphenyl) aluminate, lithium tetrakis (3,5-dimethylphenyl) aluminate, lithium tetrafluoroaluminum Nate, sodium tetrakis (pentafluorophenyl)
Aluminate, sodium tetrakis (phenyl) aluminate, sodium tetrakis (p-tolyl) aluminate, sodium tetrakis (m-tolyl) aluminate, sodium tetrakis (2,4-dimethylphenyl) aluminate, sodium tetrakis (3.5) -Dimethylphenyl) aluminate, sodium tetrafluoroaluminate, potassium tetrakis (pentafluorophenyl) aluminate, potassium tetrakis (phenyl) aluminate, potassium tetrakis (p-tolyl) aluminate, potassium tetrakis (m-tolyl)
Aluminate, potassium tetrakis (2,4-dimethylphenyl) aluminate, potassium tetrakis (3,5
Examples include, but are not limited to, aluminum compounds such as -dimethylphenyl) aluminate and potassium tetrafluoroaluminate.

The c) organoaluminum compound used in the present invention is a compound represented by the general formula (3). Specific examples of these compounds include trimethylaluminum, triethylaluminum, triisopropylaluminum, and diisopropylaluminum chloride. , Isopropyl aluminum dichloride, tributyl aluminum, triisobutyl aluminum, diisobutyl aluminum chloride, isobutyl aluminum dichloride, tri (t-butyl) aluminum, di (t-butyl) aluminum chloride, t-butyl aluminum dichloride, triamyl aluminum, diamyl aluminum Chloride, amyl aluminum dichloride and the like, but are not limited thereto.

In the present invention, as a method for preparing a catalyst from the above a) metallocene compound, b) ionized ionic compound and c) organoaluminum compound, for example, a method of mixing these compounds in an inert solvent is mentioned. However, the present invention is not limited to this.

The amount of the ionized ionic compound b) used is about 0.1 to 100 times mol, preferably about 0.5 to 30 times mol, of the metallocene compound a).

The amount of the organoaluminum compound c) is not particularly limited, but is preferably about 1 to 10000 times the mol of the metallocene compound a).

The α-olefin having 3 or more carbon atoms used in the present invention includes propylene, 1-butene,
Examples thereof include -methyl-1-pentene, 1-hexene, 1-octene, and styrene, but are not limited thereto, and may be used alone or in combination of two or more. .

Examples of the polymerization method include a solution polymerization method using a solvent and a known high-temperature high-pressure method.

The polymerization conditions for the solution polymerization method are as follows. The polymerization temperature is not particularly limited as long as it is at least 120 ° C, but is preferably from 120 to 300 ° C. Also,
The pressure during the polymerization is not particularly limited, either,
200 kg / cm ² is preferred.

In the high-pressure method, the polymerization conditions are as follows. The polymerization temperature is not particularly limited as long as it is at least 120 ° C, but is preferably from 120 to 300 ° C. Further, the pressure during the polymerization is not particularly limited, but may be 500 to 35.
00 kg / cm ² is preferred.

[0024]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

The polymerization operation, reaction, and solvent purification were all performed under an inert gas atmosphere. The solvents used in the reaction were all purified, dried and / or deoxygenated by a known method, and the compounds used in the reaction were those synthesized and identified by a known method.

Further, the ethylene / α-olefin copolymer obtained in the examples was obtained by gel permeation chromatography (GPC) (150C type manufactured by WATERS) and using TSK-GEL GMHHR-H as a column.
(S) (manufactured by Tosoh Corporation), o-dichlorobenzene was used as an eluent, and the measurement was performed under the conditions of a measurement temperature of 140 ° C, a measurement concentration of 7 mg sample / 10 ml, and o-dichlorobenzene.

Example 1 As a solvent, an aliphatic hydrocarbon (IP solvent 1620) was used.
(Idemitsu Petrochemical Co., Ltd.)) 600 ml was added to a 1 liter reactor, 20 ml of hexene was added thereto, and the temperature of the reactor was raised to 1
The temperature was set at 50 ° C. And the pressure is 20k
g / cm ² of ethylene was supplied .

On the other hand, 1 μmol of ethylenebis (indenyl) hafnium dichloride was dissolved in toluene in another container, and 250 μmol of a toluene solution of triisobutylaluminum ( triisobutylaluminum 20 wt%) in terms of aluminum was added thereto, followed by stirring for 1 hour. Next, the mixture was mixed with 2 μm of N, N-dimethylanilinium tetrakis (pentafluorophenyl) borate.
mol was added to a solution of 2 mol of toluene, and the mixture was stirred for 10 minutes. The resulting mixture was introduced into the reactor at a nitrogen pressure.

After introducing the mixture into the reactor, the reactor is
Stir at 1500 rpm for 1 hour while maintaining at 50 ° C.
A copolymerization reaction is carried out, and the obtained reaction product is treated under vacuum with 1
After drying at 00 ° C. for 6 hours, 31 g of an ethylene / hexene copolymer was obtained. Table 1 shows the measurement results such as the weight average molecular weight (Mw) of the obtained copolymer.

Comparative Example 1 A copolymer was obtained in the same manner as in Example 1, except that ethylene bis (indenyl) zirconium dichloride was used instead of ethylene bis (indenyl) hafnium dichloride. Table 1 shows the results.

Example 2 A copolymer was obtained in the same manner as in Example 1 except that the polymerization temperature was changed to 170 ° C. Table 1 shows the results.

Comparative Example 2 A copolymer was obtained in the same manner as in Comparative Example 1 except that the polymerization temperature was 170 ° C. Table 1 shows the results.

Example 3 A copolymer was obtained in the same manner as in Example 1 except that bis (cyclopentadienyl) hafnium dichloride was used instead of ethylenebis (indenyl) hafnium dichloride. Table 1 shows the results.

Comparative Example 3 A copolymer was obtained in the same manner as in Example 3 except that bis (cyclopentadienyl) zirconium dichloride was used instead of bis (cyclopentadienyl) hafnium dichloride. Table 1 shows the results.

Example 4 A copolymer was obtained in the same manner as in Example 3 except that isopropylidene (fluorenyl) (cyclopentadienyl) hafnium dichloride was used instead of bis (cyclopentadienyl) hafnium dichloride. . Table 1 shows the results.

Comparative Example 4 A copolymer was obtained in the same manner as in Example 3 except that isopropylidene (fluorenyl) (cyclopentadienyl) zirconium dichloride was used instead of bis (cyclopentadienyl) hafnium dichloride. . Table 1 shows the results.

[0037]

[Table 1]

Example 5 In this example, polymerization was carried out using a reactor equipped for high-temperature, high-pressure polymerization. Ethylene and hexene were injected into the continuous reactor, and the total pressure was set to 950 kg / cm ² and the hexene concentration was set to 34.0 mol%. And
The reactor was stirred at 1500 rpm.

On the other hand, in another container, a toluene solution of ethylenebis (indenyl) hafnium dichloride was
A toluene solution of triisobutylaluminum was added so that the aluminum content was 250 moles per hafnium . Further, a toluene solution of N, N-dimethylanilinium tetrakis (pentafluorophenyl) borate was added thereto so that the amount of boron became twice as much as hafnium , to obtain a catalyst solution .

Thereafter, the obtained catalyst solution was continuously supplied to the reactor, and polymerization was carried out by setting the temperature of the reactor to 180 ° C. Table 2 shows the results.

Example 6 Polymerization was carried out in the same manner as in Example 5, except that the polymerization temperature was 175 ° C. and the hexene concentration was 36.0 mol%. Table 2 shows the results.

Example 7 Polymerization was carried out in the same manner as in Example 5, except that the polymerization temperature was 165 ° C. and the hexene concentration was 35.0 mol%. Table 2 shows the results.

Comparative Example 5 The same procedure as in Example 5 was carried out except that ethylene bis (indenyl) zirconium dichloride was used instead of ethylene bis (indenyl) hafnium dichloride, the polymerization temperature was 155 ° C., and the hexene concentration was 32.0 mol%. Polymerization was performed by the method. Table 2 shows the results.

[0044]

[Table 2]

[0045]

When the above-mentioned hafnium metal-containing ionic metallocene catalyst is used and ethylene and an α-olefin are copolymerized under polymerization conditions of a polymerization temperature of 120 ° C. or more, the activity of the catalyst is remarkably excellent, and the efficiency of the catalyst is extremely high. Polymers can be produced.

Continuation of front page (56) References JP-A-6-100613 (JP, A) JP-A-5-155926 (JP, A) JP-A-5-140221 (JP, A) JP-A-5-43618 (JP) , A) (58) Field surveyed (Int.Cl. ⁶ , DB name) C08F 4/60-4/70

Claims (1)

(57) [Claims] An ethylene copolymerized with ethylene and an α-olefin having 3 or more carbon atoms using a catalyst for olefin polymerization comprising a) a metallocene compound, b) an ionized ionic compound and c) an organoaluminum compound. / Α
In the method for producing an olefin copolymer, a) a metallocene compound represented by the following general formula (1) or (2): Embedded image (Wherein Cp ¹ and Cp ² are each independently substituted or unsubstituted
Cyclopentadienyl group, indenyl group or fluorenyl
R ¹ is a substituted or unsubstituted alkylene group,
Alkylsilanediyl group, dialkylgermandiyl
Group, an alkyl phosphine-diyl group or an alkylimino group <br/>, R ¹ is act to crosslink Cp ¹ and Cp ^2, R ^2, R ³ are each independently hydrogen atom, a halogen atom A hydrocarbon group having 1 to 12 carbon atoms, an alkoxy group or an aryloxy group), and b) an ionized ionic compound, which is capable of converting the above metallocene compound into a cationic metallocene compound. And a compound which does not react with the formed cationic metallocene compound. C) An organoaluminum compound represented by the following general formula (3): (Wherein R ⁴ , R ^{4 ′} , and R ^{4 ″} are each independently a hydrogen atom,
A halogen atom, an amino group , an alkyl group, an alkoxy group or an aryl group, and at least one of which is an alkyl group), and polymerizing at a polymerization temperature of 120 ° C. or more. Ethylene / α-
A method for producing an olefin copolymer.