JP2956042B2 - Method for producing olefin polymer - Google Patents

Description

The present invention relates to a method for producing an olefin polymer.

(Prior Art) Conventionally, Ziegler-Natta type catalysts are generally widely known as olefin polymerization catalysts. On the other hand, little is known about complex catalysts using yttrium as the central metal.

In recent years, several reports have been made on yttrium complex catalysts having cyclopentadiene as a ligand [J. Chem. S.
oc.Chem.Commun., (1978), <22>, 994 and J. Organo
met.Chem., (1987), 323, 181]. However, any of the catalysts described in these known documents is still insufficient for activity and molecular weight control for industrial use.

(Problems to be Solved by the Invention) The present invention relates to an olefin polymerization catalyst having high activity and good activity persistence using an yttrium compound having a sterically fixed ligand, a process for producing the same, and an olefin using the same. The present invention provides a method for producing a polymer.

(Means for Solving the Problems) The present invention provides: I. General formula: CH ₂ CHCHR (where R represents a hydrogen atom or a hydrocarbon residue having 1 to 8 carbon atoms) in the presence of the following catalyst: .)
A method for producing an olefin polymer characterized by polymerizing an olefin represented by the following formula: A catalyst comprising an yttrium compound having the following components A and B: A: two cyclopentadienyl groups are mutually a hydrocarbon residue or Having a substituent bonded via a silicon atom, B: having a substituent selected from a hydrogen atom, an alkyl group and an aryl group; and 2. the catalyst is prepared by contacting the following components ab and c 2. The process for producing an olefin polymer according to claim 1, wherein component a: alkali of a compound having a divalent substituent in which two cyclopentadienyl groups are mutually bonded via a hydrocarbon residue or a silicon atom. A metal salt or an alkaline earth metal, component b: an organometallic compound of group I to group III in the periodic table, component c: yttrium halide.

(Specific Description of the Invention) [Catalyst] The catalyst of the present invention is an olefin polymerization catalyst comprising an yttrium compound having the components A and B.

Component A is that two cyclopentadienyl groups have a substituent (ligand) bonded to each other via a hydrocarbon residue or a silicon atom.

Here, the cyclopentadienyl group refers to a substituted or unsubstituted compound having a cyclopentadiene ring, specifically, a cyclopentadienyl group, an indenyl group, a phenanthrenyl group, a fluorenyl group, a bicyclo [3.3.0] octa- 1,3-dienyl group, 4,5,6,7-tetrahydroindenyl group, bicyclo [5.3.0] dec-8,11-dienyl group, tricyclo [5.2.1.0 ^2,6 ] deca-2,5- Examples thereof include a dienyl group and an alkyl, alkylsilyl or alkylgermyl-substituted product thereof. Above all,
A substituted or unsubstituted cyclopentadienyl group, indenyl group, fluorenyl group, or 4,5,6,7-tetrahydroindenyl group is preferred.

In addition, a hydrocarbon residue or a silicon atom is used to bond the two cyclopentadienyl groups. Here, the hydrocarbon residue preferably has 1 to 4 carbon atoms in the main chain.
Or an alkyl group or an aryl-substituted product thereof. Also, those bonded by a silicon atom are preferably dialkyl or aryl-substituted silyl groups. Among them, methylene, dimethylmethylene, ethylene, tetramethylethylene, propylene, dimethylsilyl, and diphenylsilyl groups are preferred.

Component B has a substituent selected from a hydrogen atom, an alkyl group, and an aryl group. As the alkyl group, an alkyl group having 1 to 12 carbon atoms, preferably an alkyl group having 1 to 8 carbon atoms or an alkyl (C 1 to 8) substituted silicon group, and an aryl group having 6 to 18 carbon atoms, Preferably, an aryl group having 6 to 12 carbon atoms or an aryl group having alkyl (1 to 8 carbon atoms) substituted silicon is exemplified.

Among these, a sterically bulky substituent, for example, an alkyl group having 1 to 8 carbon atoms or an alkyl (having 1 carbon atom at the α-position)
To 8) an alkyl group or an ortho-substituted aryl group preferably having a plurality of substituted silyl groups, and a structure having a structure in which β-hydrogen or alkyl elimination hardly occurs, such as a trialkylsilyl-substituted methyl group and an ortho-substituted aryl group And the like, and specific examples thereof include a bistrimethylsilylmethyl group and a mesityl group.

The catalyst having the above components A and B can be specifically prepared using the following components a, b and c having the respective components.

Component a having component A is an alkali metal or alkaline earth metal salt of a compound having a divalent substituent in which two cyclopentadienyl groups are mutually bonded via a hydrocarbon residue or a silicon atom. is there.

 The preferred component a is specifically represented by the general formula M ₁C p-Q-C ' p M ₂ It is a compound represented by these. Where Q is a hydrocarbon residue
Or a silicon atom. Cp and C'p are the same but different
Represents a cyclopentadienyl group which may be present. M₁And M_Two
Are the same or different alkali metals or alka
Lithium earth metals are shown respectively. Note that M₁And M_TwoBut Arca
In the case of lithium earth metals, halogen or alkali groups
It is necessary that each is bonded. Where M₁And
And M_TwoIs preferably lithium, sodium, potassium,
Such as magnesium.

Specific examples of the component a include methylenebis (cyclopentadienyl) dilithium, ethylenebis (cyclopentadienyl) dilithium, ethylenebis (2-methylcyclopentadienyl) dilithium, ethylenebis (3-
Methylcyclopentadienyl) dilithium, ethylenebis (2,3-dimethylcyclopentadienyl) dilithium, ethylenebis (2,4-dimethylcyclopentadienyl) dilithium, ethylenebis (2,3,4-trimethylcyclo) Pentadienyl) dilithium, ethylenebis (2,
3,5-trimethylcyclopentadienyl) dilithium,
Ethylenebis (2,3,4,5-tetramethylcyclopentadienyl) dilithium, ethylenebis (3-ethylcyclopentadienyl) dilithium, ethylenebis (3-t-
Butylcyclopentadienyl) dilithium, ethylenebis (3-phenylcyclopentadienyl) dilithium,
Ethylene bis (3-benzylcyclopentadienyl) dilithium, ethylenebis (3-methylcyclopentadienyl) dilithium, isopropylidenebis (cyclopentadienyl) dilithium, 1,3-propylenebis (cyclopentadienyl) dilithium Dimethylsilylenebis (cyclopentadienyl) dilithium, dimethylsilylenebis (2,3,4,5-tetramethylcyclopentadienyl) dilithium, diphenylsilylenebis (2,3,4,5-
Tetramethylcyclopetadienyl) dilithium, dimethylsilylene (cyclopentadienyl-2,3,4,5-tetramethylcyclopentadienyl) dilithium, dimethylsilylenebis (3-trimethylcyclopentadienyl) dilithium, cyclohexyl Denbis (3-methylcyclopentadienyl) dilithium, ethylene bis (indenyl) dilithium, ethylene bis (indenyl) disodium, ethylene bis (indenyl) dipotassium, ethylene bis (indenyl) dim magnesium chloride, ethylene bis (indenyl) di Magnesium bromide, ethylenebis (2-methylindenyl) dilithium, ethylenebis (3-methylindenyl) dilithium, ethylenebis (4-methylindenyl) dilithium, ethylenebis (7-methylindenyl) Le) dilithium, methylenebis (indenyl) dilithium, 1,3-propylenebis (indenyl) dilithium, isopropylidenebis (indenyl) dilithium, diphenylmethylenebis (indenyl) dilithium, cyclohexylidenebis (indenyl) dilithium, ethylenebis ( 4,5,6,7-tetrahydroindenyl) dilithium, ethylenebis (fluorenyl) dilithium, 2,2-propylene (cyclohexylidenebis, fluorenyl) dilithium, dimethylsilyl (bisindenyl) dilithium, dimethylsilyl (4,5,
Examples thereof include 6,7-tetrahydroindenyl) dilithium and dimethylsilyl (cyclopentadienyl, fluorenyl) dilithium.

Component b having component B is preferably an organometallic compound having a substituent selected from an alkyl group and an aryl group, and preferably belongs to Groups I to III of the periodic table.

Specific examples of the component b include methyl lithium, methyl potassium, methyl sodium, methyl magnesium chloride, methyl magnesium bromide, methyl magnesium iodide, ethyl lithium, diethyl magnesium, n
-Butyllithium, sec-butyllithium, tert-butyllithium, isoprenyllithium, neopentyllithium, di-tert-butylmethyllithium, phenyllithium, o-tolyllithium, 2,6-dimethylphenyllithium, mesityllithium, o-ethylphenyllithium, o-tert-butylphenyllithium, o-trimethylsilylphenyllithium, benzyllithium, neofillithium, trimethylsilylmethyllithium, bistrimethylsilylmethyllithium, trimethylaluminum, triethylaluminum, triisobutylaluminum, dimethylaluminum chloride, Ethyl aluminum sesquichloride, diethyl aluminum hydride, diisobutyl aluminum hydride, methyl aluminoxane, triethyl boron Etc. it is this an example of the. Of these, alkali metal or alkaline earth metal salts of tolylalkylsilyl-substituted methyl groups such as bistrimethylsilylmethyllithium and ortho-substituted aryl groups such as methyllithium are preferred.

Component c is a yttrium halide. Specific examples include yttrium trichloride, yttrium tribromide,
Examples include yttrium triiodide. Among them, yttrium trichloride is preferable.

The catalyst used in the present invention can be synthesized by applying a known technique. For example, preferably, the compound of the above-mentioned component a is mixed with an ether-based organic solvent such as tetrahydrofuran, diethyl ether, dimethoxyethane, etc.
In the presence of a 1000-fold organic solvent), the compound of component c
It is obtained by contacting components a: component c at a ratio (molar ratio) of 0.5: 1 to 1.25: 1 in a temperature range of 〜200 ° C. and reacting component b with the obtained product. Solvents used in this reaction are, for example, pentane, hexane, aliphatic hydrocarbons such as heptane, alicyclic hydrocarbons such as cyclohexane, benzene,
Using an aromatic hydrocarbon solvent such as toluene or the above-mentioned ether-based organic solvent (an organic solvent having a weight ratio of 5 to 1000 times that of the component b), the amount of the component b used is based on the component c used first. The reaction temperature is -200.
~ 200 ° C.

In the production of the catalyst, when an alkali metal or alkaline earth metal compound having an alkyl group or an aryl group is used as the component b, hydrogen gas can be used simultaneously with or after the reaction of the component b. .

The above-mentioned catalyst of the present invention can be used for polymerization as it is as a reaction product, but may be supported on a suitable support. As a support used at this time, an inorganic carrier such as silica gel, alumina, zeolite, magnesium chloride, and magnesium oxide and a polymer carrier such as polyethylene particles and polypropylene particles can be used.

〔polymerization〕

The monomer polymerized using the yttrium catalyst of the present invention is an olefin compound having a terminal double bond represented by the general formula CH ₂ CHCH—R. Here, R represents a hydrogen atom or a hydrocarbon residue having 1 to 8 carbon atoms. Specifically, ethylene, propylene, 1-butene, 3-methylbutene-1, 1-hexene, 4-methylpentene-1, 1
-Octene, 1-decene, styrene, butadiene, isoprene, 1,5-hexadiene, 7-methyl-1,7-octadiene and the like can be exemplified. These monomers may be used alone or in combination of two or more.

The polymerization may be performed in a gas phase, a liquid phase, or any other known method. When a solvent is used, an inert organic solvent is preferably used. For example, aromatic hydrocarbon solvents such as benzene, toluene, and xylene, n-pentane, n-hexane, and n
Aliphatic hydrocarbon solvents such as heptane and n-paraffin; and cycloaliphatic hydrocarbon solvents such as cyclohexane and methylcyclopentane. One of the features of the present invention is that an aliphatic hydrocarbon solvent is also effective.

The polymerization temperature is between -20 and 260C, preferably between 40 and 200C.

In the polymerization, a molecular weight regulator can be used. Hydrogen gas is effective as a molecular weight regulator. In addition, since hydrogen has a catalytic activity improving effect, it is preferable that hydrogen is present in the polymerization system.

The polymerization pressure is appropriately selected in the range from normal pressure to 3000 kg / cm ² G.

(Effects of the Invention) According to the present invention, by using a novel yttrium compound having a specific ligand, an olefin polymerization catalyst having high activity and excellent activity persistence can be obtained, and the molecular weight distribution is narrow and the molecular weight distribution is low. Olefin polymers having a wide range of molecular weights up to high molecular weights can be produced.

(Examples) Example-1 Production of Catalyst In a 300 ml flask equipped with stirring blades sufficiently purged with nitrogen,
10.0 mmol of 1,2-diindenylethane and 120 ml of purified THF were added, the mixture was cooled to −78 ° C., and 12.5 ml of a 1.6 M hexane solution of n-butyllithium was added dropwise. Raise the temperature to room temperature, 8
Allowed to react for hours.

To this, 1.95 g of anhydrous yttrium chloride was added at -78 ° C for 1 hour.
A slurry made with 00 ml of THF was added at 0 ° C. and refluxed for 8 hours.

After the completion of the reaction, the mixture was cooled to 10 ° C and the solvent was distilled off under reduced pressure. After adding 100 ml of purified diethyl ether thereto and stirring, the mixture was cooled to 10 ° C., and the solvent was distilled off under reduced pressure. This operation was repeated twice.

100 ml of purified toluene was added to the obtained product, and 15.0 ml of a bistrimethylsilylmethyllithium 0.67M-diethyl ether solution was added at 0 ° C., and the mixture was reacted for 8 hours. After distilling off the solvent of the reaction product under reduced pressure, purified toluene 100m
The mixture was extracted with l, concentrated, concentrated and recrystallized to obtain a product.

The resulting product was diluted in purified toluene to give 0.063 m
It was subjected to polymerization as a catalyst solution of mol-Y / ml-toluene.

Polymerization 300 ml of purified toluene was introduced into an autoclave with stirring blades which had been sufficiently dried and purged with nitrogen, and then 2.5 ml (0.157 mmol) of the catalyst solution prepared above was added under a nitrogen atmosphere. / cm ² G and stirred at 15 ° C. for 1 hour. Next, after purging with hydrogen and purging the system with nitrogen, ethylene was introduced, and the pressure in the polymerization tank was increased to 6 kg / cm ² G.
And polymerized at 80 ° C. for 3 hours.

As a result, 66.6 g of polyethylene was obtained, and its molecular weight was Mn of 2.40 × 10 ⁴ , Mw of 5.90 × 10 ⁴ , and Q value (Mw / Mn).
Was 2.46.

Example 2 Polymerization The same autoclave as in Example 1 was sufficiently dried and purged with nitrogen, and 300 ml of purified toluene and 2.5 ml (0.157 mmol) of the catalyst solution used in Example 1 were introduced.
1200 ml and ethylene were introduced, and polymerization was carried out at 60 ° C. for 3 hours while maintaining the polymerization tank pressure at 8 kg / cm ² G.

As a result, 37.2 g of polyethylene was obtained, and the molecular weight was 1.31 × 10 ^{4 for} Mn, 2.96 × 10 ^{4 for} Mw, and the Q value was 2.26.

Example 3 Polymerization In the same manner as in Example 1, 5 ml of the catalyst solution (0.31 mmo) was used.
l) and polymerized at 60 ° C. with propylene.

After completion of the polymerization, the solvent was distilled off to obtain 0.47 g of a polymer. The product was confirmed to be actic polypropylene by 13-NMR.

Example 4 Preparation of Catalyst In the same manner as in Example 1, a dimethylsilylenebisindene 10.0 mmol and purified THF 150 ml were put into a 300-ml flask equipped with a stirring blade sufficiently purged with nitrogen, and cooled to −78 ° C.
14.0 ml of a 1.6 M hexane solution of n-butyllithium was added dropwise. The reaction mixture was warmed to room temperature and reacted for 8 hours.

To this, 1.95 g of anhydrous yttrium chloride was added at -78 ° C for 7 minutes.
The slurry made with 5 ml of THF was added to 0 ° C. and refluxed for 8 hours.

After the completion of the reaction, the mixture was cooled to 10 ° C and the solvent was distilled off under reduced pressure. 120 ml of purified diethyl ether was added thereto, extracted, and the solvent was distilled off to obtain 3.34 g of a brown reaction product.

100 ml of purified toluene was added to the obtained product, and 10.3 ml of a 0.53 M solution of bistrimethylsilylmethyllithium in diethyl ether was added at 0 ° C., and the mixture was reacted for 8 hours. After distilling off the solvent of the reaction product under reduced pressure, purified toluene 100m
The mixture was extracted with l and passed for polymerization.

Its catalyst concentration was 0.067 mmol-Y / ml-toluene.

Polymerization In the same manner as in Example 1, 5.0 ml of the catalyst solution (0.337 mmol
l) and polymerized at 60 ° C. with ethylene.

As a result, 31.6 g of polyethylene was obtained, and the molecular weight was 1.48 × 10 ^{5 for} Mn, 4.57 × 10 ^{5 for} Mw, and the Q value was 3.08.

Example-5 In the same manner as in Example-4, polymerization was carried out in the presence of 15 ml (in terms of liquid) of propylene during ethylene polymerization.

As a result, 11.8 g of a polymer was obtained, and the molecular weight was Mn of 6.82 × 10 ⁴ , Mw of 2.04 × 10 ⁵ , and Q value of 2.99.

Example -6 Preparation of catalyst In the same manner as in Example-4, 8.5 mmol of dimethylsilylene (cyclopentadiene, fluorene) and 150 ml of purified THF were placed in a 300 ml flask equipped with a stirring blade and sufficiently purged with nitrogen. After cooling, 11.1 ml of a 1.6 M hexane solution of n-butyllithium was added dropwise. The temperature of the reaction mixture was raised to room temperature and reacted for 8 hours.

To this, 1.65 g of anhydrous yttrium chloride was added at -78 ° C for 5 minutes.
A slurry made with 0 ml of THF was added at 0 ° C. and refluxed for 8 hours.

After the completion of the reaction, the product was cooled to 10 ° C., and the solvent was distilled off under reduced pressure. 100 ml of purified diethyl ether was added to this,
After stirring, the solvent was again distilled off under reduced pressure. This operation was repeated twice.

100 ml of purified toluene was added to the obtained product, 12.6 ml of a bistrimethylsilylmethyllithium 0.67M-diethyl ether solution was added at 0 ° C., and the mixture was reacted for 8 hours. After distilling off the solvent of the reaction product under reduced pressure, purified n-pentane
After washing with 75 ml, the mixture was further extracted with 100 ml of purified toluene and passed through for polymerization.

The catalyst concentration of this was 0.045 mmol-Y / ml-toluene.

Polymerization In the same manner as in Example 1, 5.0 ml of the catalyst solution (0.225 mmol
l) and polymerized at 25 ° C. with ethylene.

As a result, 5.0 g of polyethylene was obtained, and the molecular weight was Mn of 2.12 × 10 ⁵ , Mw of 5.80 × 10 ⁵ , and Q value of 2.74.

──────────────────────────────────────────────────の Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) C08F 4/52-4/70 CA (STN)

Claims (2)

(57) [Claims] 1. A compound of the general formula: CH ₂ CHCHR in the presence of the following catalyst:
(Wherein, R represents a hydrogen atom or a hydrocarbon residue having 1 to 8 carbon atoms). A process for producing an olefin polymer characterized by polymerizing an olefin represented by the following formula: Catalyst comprising an yttrium compound: A: two cyclopentadienyl groups having a substituent bonded to each other via a hydrocarbon residue or a silicon atom, B: substitution selected from a hydrogen atom, an alkyl group and an aryl group Having a group. 2. The process for producing an olefin polymer according to claim 1, wherein said catalyst is prepared by contacting the following components a and c: Component a: two cyclopentadienyl groups are mutually hydrocarbons An alkali metal salt or an alkaline earth metal of a compound having a divalent substituent bonded through a residue or a silicon atom, component b: an organometallic compound of Groups I to III of the periodic table, and component c: yttrium halide.