JPH0253805A - Method of polymerization - Google Patents

Abstract

PURPOSE:To obtain in high activity an olefin polymer in an industrially advantageous manner by using, as a catalyst, a reaction product from a specific transition metal compound, an organic aluminum compound and water with good hand liability and storage stability of said catalyst. CONSTITUTION:An olefin is polymerized using, as a catalyst, a reaction product from a transition metal (group IVA metal) compound [e.g., tetrabenzyltitanium (IV)], an organoaluminum compound (e.g., trimethylaluminum) and water. For each constituent of said catalyst, it is preferable that the molar ratio Al/ transition metal atom is (1:10)-(1:10<-8>) and the molar ratio (Al + transition metal atom)/water is (1:1)-(2:1). Said reaction product can be prepared by e.g., direct reaction between the respective components in an organic solvent.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for polymerizing olefins. More specifically, the present invention relates to a method for polymerizing olefins using a transition metal catalyst and an organic aluminum catalyst.

[Prior art]

Catalysts that combine many types of transition metal compounds and organometallic compounds have been known for a long time, but recently, catalysts with unprecedented properties such as dicyclopentagenyl titanium dichloride, dicyclopentagenyl titanium dimethyl, dicyclopentadienyl zirconium dichlorite, dicyclopentadienyl zirconium dimethyl,
It has been proposed that olefins can be polymerized by using a homogeneous catalyst consisting of a transition metal compound such as dicyclopentadienyl hafnium dichloride or dicyclopentadienyl hafnium dimethyl and aluminoxane (Japanese Patent Application Laid-Open No. 19303/1983, etc.) .

[Problem to be solved by the invention]

In the above method, extremely high polymerization activity per transition metal compound can be obtained for olefin polymerization.

However, the aluminoxane used here is highly reactive and becomes inactive when mixed with a small amount of water, so there are problems in handling, such as difficulty in long-term storage.

Furthermore, although the catalyst may be prepared by mixing a transition metal compound and aluminoxane, it is necessary to immediately subject the mixed solution to polymerization after preparing the catalyst.

It is known that if for some reason the mixed liquid cannot be subjected to polymerization immediately after catalyst preparation, the activity of the catalyst will drop rapidly and become inactive. Therefore, there is a need for a catalyst that is stable and easy to handle.

[Means for Solving the Problems] The inventors of the present invention made extensive studies to solve the above problems, and found that a catalyst system consisting of a combination of a transition metal compound, an alkyl aluminum, and water is capable of polymerizing olefins. The present invention was completed based on the discovery that it exhibits high properties, is storage stable, and is easy to handle.

That is, the present invention is a method for polymerizing olefins, which is characterized in that a reaction product of a group transition metal compound of Table 1■Δ, an organoaluminum compound, and water is used as a catalyst.

The transition metal compound of Group IVA of the periodic table used in the present invention is a titanium, zirconium or hafnyl compound having at least one hydrocarbon group as a ligand. Examples of the hydrocarbon group include σ ligands such as alkyl groups and aryl groups, and ligands such as π enyl and π cyclopentagenyl.

Specifically, tetrahensyl titanium (IV), hiss (η-
7 clopenter/enyl) titanium (11), dichloro(
η-cyclopentagenyl) titanium ([11), chlorobis(η-cyclopentagenyl) titanium (Ill),
) dichloro(η-cyclopentadienyl)titanium (IV
), dichlorobis(η-cyclopentadienyl)titanium (TV), dimethylbis(η-cyclopentagenyl)titanium(IV), bis(phenylethyl)bis(
η-cyclopentadienyl) titanium (TV), bis(
η-cyclopentagenyl) titanium (IV), tetrabenzylzirconium, tetrakisallylzirconium (TV), trichloro(η-cyclopentagenyl)zirconium (■), dichlorobis(η-cyclopentagenyl)zirconium (IV) , dimethylbis(η-cyclopentagenyl)zirconium(IV), chlorobis(η-cyclopentagenyl)zirconium(IV)
Oxide, dichlorobis(η-cyclopentagenyl)
Examples include zirconium (IV), tetrakisallyl hafnium (■), dichlorobis(η-cyclopentadienyl) hafnium (IV), dimethylbis(η-cyclopentagenyl) hafnium (IV), and the like.

The organoaluminum compound used in the present invention is a trialkylaluminum represented by the general formula AlR3, and specifically, trimethylaluminum, triethylaluminum, tripropylaluminum, tri-n-butylaluminum, triisobutylaluminum. J1, trihexylaluminum, or a mixture thereof.

In the present invention, a catalyst is obtained by reacting a transition metal compound and an organoaluminum compound with water in the presence or absence of a solvent inert to these compounds.

There are no particular restrictions on the method for producing the catalyst component, such as a method in which a transition metal compound is directly reacted with a trialkylaluminum represented by the general formula AlR3 by dissolving water in a liquid, solid, steam, or solvent in an organic solvent. Alternatively, a compound containing adsorbed water or water of crystallization, such as copper sulfate hydrate, aluminum sulfate hydrate, or iron sulfate hydrate, is reacted with a transition metal compound and trialkyl alumina J in a solvent. Examples include methods of manufacturing.

Such solvents include hydrocarbon solvents. Specifically, hydrocarbon solvents include hydrocarbons such as butane, pentane, hexane, heptane, octane, decane, dodecane, cyclohexane, cyclooctane, Hensen, toluene, xylene, and petroleum distillates such as gasoline, kerosene, and light oil. used. In addition, the reaction ratio of the transition metal compound used in this reaction, the organoaluminum compound, and water is such that the ratio of aluminum to transition metal atoms is 1:10 to 1:10.
It is preferable to use it within the range of -1'. Further, it is appropriate that the ratio of water used is such that the ratio of the total number of moles of aluminum and transition metal atoms to the number of moles of water is in the range of 1:1 to 2:1.

In the polymerization reaction, the obtained product may be used as it is, but it can also be further purified and used in a state with less solvent and unreacted trialkylaluminum, which is preferable depending on the case.

In the present invention, specific examples of olefins used in polymerization include ethylene, propylene, l-butene, 4-methyl-1-pentene, ■-hexene, 1-octene, 1
α-olefins such as -decene, ■-dodecene, 1-tetradecene, l-hexadecene, ■-octadecene, styrene, methylstyrene, α-vinylnaphthalene, β-
Examples include hinylnaphthalene. When producing a copolymer, more than one of these components can be mixed and used.

In the polymerization method of the present invention, suspension polymerization, bulk polymerization, and gas phase polymerization are employed for olefin polymerization. In the suspension polymerization method, a hydrocarbon medium is used, and specific examples of the hydrocarbon medium include butane, pentane, hexano, heptano, octane, decane, dodecane, cyclohexane,
Hydrocarbons such as cyclooctane, Hensen, toluene, and xolene, and petroleum distillates such as gasoline, kerosene, and light oil are used. When polymerizing in a liquid phase, including bulk polymerization using a liquid monomer as a medium, it is usually 10-' to 10-
'mo! It is preferable to use an aluminum compound concentration of /ρ.

As the polymerization temperature and pressure, general conditions used in known methods are used, and the temperature is -50 to 300°C.
1 Preferably, the temperature range is from -20 to 200°C. The polymerization pressure is normal pressure to 50 kg/c+fl gauge. The average molecular weight of the resulting polymer can be adjusted in a known manner by adding hydrogen and/or adjusting the polymerization temperature.

〔Example〕

The present invention will be further explained below with reference to Examples.

Example-1 (a) Preparation of catalyst components Trimethylaluminum (1,38 mol/j! concentration) diluted with toluene was placed in a Pyrex glass container with an internal volume of 50 mm, which had been thoroughly dried and purged with nitrogen.
0.91 g of ferrous sulfate heptahydrate (Fez(SO2)a 7HzO)
mmol) was added.

Furthermore, 50 mg (0.14 mmol) of dichlorobis(η-cyclopentadienyl)zirconium(IV) was added, and the temperature of the solution was raised to 50° C. and the reaction was carried out for 4 hours. After the temperature was returned to room temperature, insoluble materials were removed to obtain a catalyst component.

(b) Polymerization of styrene 25 ml of styrene was placed in a Pyrex glass autoclave with an internal volume of 300 mR that had been thoroughly dried and purged with nitrogen.
was added, and the catalyst component (a) (0.017 mmo+ in terms of zirconium atoms) was added, followed by stirring at room temperature. Polymerization was continued for 2 hours at 25°C. Add a small amount of methanol to the autoclave to stop the ζ polymerization and reduce the contents to 50%
The mixture was poured into 0 ml of methanol acidified with hydrochloric acid, and insoluble matter was filtered to obtain white powdered polystyrene.

The yield of this powdered polystyrene is 0.42 g, and the activity is therefore 12.4 kg/mol .Zr .hr.

Example 2 In Example 1, ethylene was polymerized in the same manner as in Example 1 (b) except that ethylene was used instead of styrene. That is, the above catalyst (a) (0.045 mmol in terms of zirconium atoms) was charged into 660 mff1 of toluene in a 5US-32 autoclave having an internal volume of 2N which had been thoroughly dried and purged with nitrogen. The contents of the autoclave were heated and polymerization was continued for 1 hour while charging ethylene to maintain the polymerization pressure at 5 kg/cJ-gauge at 5°C.The autoclave was cooled and unreacted ethylene was removed. After purging, the contents were poured into 1! of methanol, and insoluble matter was filtered to obtain white powdery polyethylene.

The yield of this powdered polyethylene is 14.8 g, so the activity is 329 kg/mol-Zr-hr.

Example-3 (a) Preparation of catalyst components In Example-1, dichlorobis(η-cyclopentagenyl)titanium (TV) 6 was used as the transition metal catalyst.
．． 6 mg (0,027 mmol) of dichlorobis (
A catalyst component was synthesized in the same manner as in Example 1(a), except that ηcyclopentadienyl)zirconium (TV) was used instead.

(t)) Polymerization of styrene 25 m of styrene was placed in a Pyrex glass autoclave with an internal volume of 300 d, thoroughly dried and purged with nitrogen! was added, and the catalyst component (a) (0.0066 mmol in terms of titanium atoms) was added, followed by stirring at room temperature. Polymerization was continued for 2 hours at 25°C. Add a small amount of methanol to the autoclave to stop the polymerization and reduce the contents to 50%
The mixture was poured into 0 ml of methanol acidified with hydrochloric acid, and insoluble matter was filtered to obtain white powdered polystyrene.

The yield of this powdered polystyrene was 0.2 h, and therefore the activity was 21.2 kg/mol·Ti-hr.

Example 4 In Example 3, ethylene was polymerized in the same manner as in Example 3 (b) except that ethylene was used instead of styrene. That is, the above catalyst component (a) (0.009 mmol in terms of titanium atoms) was charged into 660 mff of toluene in a 5US-32 autoclave with an internal volume of 2ρ that had been sufficiently dried and purged with nitrogen.The contents of the autoclave was heated to a polymerization pressure of 5 at 35°C.
Polymerization was continued for 1 hour while charging ethylene to maintain kg/ctRl gauge. Cool the O-l-crepe, purge unreacted ethylene, and reduce the contents to 1!
The mixture was poured into methanol, and insoluble matter was filtered to obtain white powdery polyethylene.

The yield of this powdered polyethylene is 7.1 g, so the activity is 788 kg/molTi + hr.

Comparative Example 1 (a) Preparation of catalyst component In Example 1, a catalyst component was synthesized in the same manner as in Example 1(a) except that the transition metal catalyst component was not used.

(b) Polymerization of ethylene Ethylene was polymerized in the same manner as in (b) of Example-1. In other words, the internal volume is 2! which has been thoroughly dried and replaced with nitrogen! Toluene 66 in an autoclave made of 5O3-32
The above catalyst component (a) (7.7 mmol in terms of aluminum atoms) was charged into the 0rd. Heat the contents of the autoclave to a polymerization pressure of 5 kg/c+I at 50°C.
Polymerization was continued for 1 hour while charging ethylene to maintain I gauge. The autoclave was cooled, unreacted ethylene was purged, and the contents were poured into 11 methanol. No polyethylene was obtained.

Comparative Example 2 (a) Preparation of Catalyst Component In Example 1, a catalyst component was synthesized in the same manner as in Example 1(a) except that trimethylalumina J. was not used.

(b) Polymerization of ethylene Ethylene was polymerized in the same manner as in (b) of Example-1. In other words, the internal volume is 2! which has been thoroughly dried and replaced with nitrogen! Toluene 66 in an autoclave made of 5O5-32
The above catalyst component (a) (0.045 mmol in terms of zirconium atoms) was charged into 0mff1. The contents of the autoclave were heated to 50°C and the polymerization pressure was increased to 5 kg/kg.
Polymerization was continued for 1 hour while charging ethylene to maintain the Cd gauge. Cool the autoclave, purge unreacted ethylene, and reduce the contents to 1! of methanol. No polyethylene was obtained.

Reference Example-1 As a transition metal compound, dichlorobis(η-cyclopentadienyl)zirconium (m (hereinafter, CpZrCl
Polymerization was carried out in the same manner as in Example 2, except that 0.032 mmol (abbreviated as Z) and 4.8 mmol of methylaluminoxane synthesized by the method of Comparative Example 1 were used to obtain 13.6 g of polyethylene. Activity is 425kg/mol
・It was Zr-hr.

Comparative Example 3 The same procedure as Reference Example 1 was conducted except that CpZrCl 2 and methylaluminoxane were mixed at 25° C. for 1 hour in 10 me of toluene, and then ethylene was polymerized, to obtain 5.6 g of polyethylene. Activity is 175kg/mol'Z
It was r.hr.

Comparative Example 4 Comparative Example 3 was repeated except that CpTiCIz was used instead of CpZrClz, but no polyethylene was obtained.

〔Effect of the invention〕

The catalyst component used in the method of the present invention can be easily synthesized,
It is stable and easy to handle, and it is possible to obtain polymers with high activity, so it has high industrial value.

Patent applicant Mitsui Toatsu Chemical Co., Ltd.

[Brief explanation of the drawing]

FIG. 1 is a diagram to help explain the invention in detail.

Claims (1)

[Claims] A method for polymerizing olefins, characterized in that a reaction product of a group IVA transition metal compound of the periodic table, an organoaluminium compound, and water is used as a catalyst.