JPH04114006A - Polymerization of alpha-olefin - Google Patents

Abstract

PURPOSE:To obtain the subject polymer having a high stereoregularity by using a solid catalyst composed of a titanium compound supported on a magnesium compound, a stereoregularity-improving agent consisting of a specified organic transient metal compound and an organoaluminum-containing high-activity catalyst. CONSTITUTION:In polymerization of an alpha-olefin in the presence of a solid catalyst composed of a titanium compound supported on a magnesium compound, a stereoregularity-improving agent and a catalyst consisting of an organic aluminum-containing catalyst, the alpha-olefin is polymerized using, as the stereoregularity-improving agent, an organic transition metal compound represented by formula I (A and B are aromatic hydrocarbon; X is halogen or 1-20C hydrocarbon residue; M is metal atom selected from IV and V group in the periodic table) or formula II (R is compound connecting A to B and containing 1-20C hydrocarbon residue, silicon, germanium or tin). An objective polymer can be obtained thereby.

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 an improved polymerization method for polymerizing α-olefins using a supported transition metal catalyst, an organoaluminium, and a stereoregularity improver.

[Prior art]

Many improvements have been made since Japanese Patent Publication No. 39-12105 proposed a method using a catalyst consisting of a supported type transition metal compound and organoaluminium as a polymerization catalyst for α-olefins, and an organic acid ester as a stereoregularity improver. Catalysts have been proposed, and both the catalytic activity and the stereoregularity of the resulting polymers have been significantly improved. On the other hand, a catalyst system combining aluminum-free titanium trichloride and an organic titanium compound was disclosed in U.S. Patent No. 2,992,
No. 212 and JP-A-57-111307.

Regarding the catalyst system that combines aluminum-free titanium trichloride and an organic titanium compound, instead of titanium trichloride, a catalyst system that combines a catalyst with a titanium compound supported on magnesium chloride and an organic titanium compound is used as a solid catalyst component. High activity per titanium inside,
There are also reports that α-olefin polymers with high stereoregularity can be obtained. (For example, Soga et al., Makrom
ol, Chem.

Rapid Coffimun, 1986, Volume 7, 71
(p. 9) Furthermore, a highly active and highly stereoregular polymer can be obtained by polymerizing α-olefins with a solid catalyst component containing magnesium, titanium, and halogen as essential components, an organic titanium compound, and a catalyst consisting of aluminoxane. has been proposed in Japanese Patent Application Laid-Open No. 1-217012.

[Problem to be solved by the invention]

However, the method of adding an organic acid ester during polymerization has problems such as leaving a characteristic ester odor in the polymer and causing coloration. On the other hand, a catalyst system that combines a catalyst with a titanium compound supported on magnesium chloride and a 1R titanium compound does not use organic acid ester, so there is no such problem, but the polymerization activity is insufficient and the catalyst residue is completely lost. It is difficult to commercialize the product without removing it, and it is desired to further improve the catalyst activity. Furthermore, although the method using aluminoxane improves the polymerization activity, it uses expensive aluminoxane, so there is a problem that the cost of the obtained polymer increases. Furthermore, since organic titanium compounds are unstable and easily decompose, it is desirable to use more stable organic transition metal compounds such as organic zirconium compounds, organic hafnium, and organic vanadium compounds. However, these compounds could not be used because of problems such as a decrease in catalytic activity and a significant decrease in stereoregularity (for example, Soga et al., Makromol, Ches+, 1989, Vol. 190, pp. 31-35). ).

[Means to solve the problem]

In order to solve the above problems, the present inventors conducted extensive studies and found that even if the same carrier-type transition metal catalyst is used, an organic aluminum compound and an organic transition metal compound as a stereoregularity improver can be used in combination at the same time. The present invention was completed by discovering that it is possible to produce a highly active and highly stereoregular α-olefin polymer by the following method. The object of the present invention is to provide a method for producing highly active and highly stereoregular poly-α-olefins.

That is, the present invention provides a method for polymerizing α-olefin using a solid catalyst consisting of a titanium compound supported on a magnesium compound, a stereoregularity improver, and a catalyst consisting of an organoaluminum, in which as the stereoregularity improver, A and B are the same or different aromatic hydrocarbons, P is a hydrocarbon residue having 1 to 20 carbon atoms connecting A and B, or a compound containing silicon, germanium, or tin;
X is a halogen atom or a hydrocarbon residue having 1 to 20 carbon atoms. A is a metal atom selected from Group 4.5 of the periodic table. )
This is a method for polymerizing α-olefins, which is characterized by using an organic transition metal compound represented by:

There are no particular limitations on the method for producing the titanium compound solid catalyst component supported on the magnesium compound used in the present invention, and the resulting catalyst is a highly active and highly stereoregular poly-α
- Anything that gives olefins is fine.

Here, any magnesium compound can be used as long as it does not react with the transition metal compound and become inactive, such as magnesium chloride, magnesium bromide, magnesium iodide, magnesium oxide, and perchloric acid. Salts such as magnesium, magnesium hydroxide, magnesium carbonate, and magnesium hydride, and complex salts thereof, as well as complex oxides with metal oxides such as silica, alumina, and titania, can also be used. The size of these magnesium compounds is preferably 1 μm to 0.1 μm in diameter. Preferably anhydrides are used here. The magnesium compound can be further calcined before use, and it is preferable to use it after at least free water is removed. For example, magnesium chloride is preferred among the magnesium compounds, and magnesium chloride alone or a complex of magnesium chloride and an electron donor may be used.

Examples of the titanium compound used in the present invention include titanium tetrahalide, alkoxytitanium halide, allyloxytitanium halide, and alkoxytitanium. Among these, halogenated titanium compounds are preferred, and titanium tetrachloride or a complex of titanium tetrachloride and an electron donor is more preferably used. The electron donor used in the complex of magnesium chloride and an electron donor or the complex of titanium tetrachloride and an electron donor is usually a C-O bond, a C-
Examples include compounds containing N bonds.

There is no particular restriction on the method of bringing the titanium compound into contact with the magnesium compound to form a solid catalyst component in the present invention, and the contact may be carried out in a solvent or in a solid phase.

As a method of contacting in a solvent, a magnesium compound is suspended in an inert solvent such as a hydrocarbon solvent,
A method in which a liquid titanium compound is added and stirred, a method in which a liquid titanium compound is reacted with a liquid magnesium compound, and a method in which a liquid titanium compound is obtained from a mixed solution of these compounds using an appropriate precipitant are also used. In these cases, Sin
g, A1.0. It is also possible to coexist a solid compound such as , AlC1z.

An example of a method for contacting in a solid phase is a method of co-pulverization. There are no particular restrictions on the method of co-pulverization, and commonly used methods using ball mills, vibration mills, etc. can be used as is. It is also possible to use various organic compounds as grinding aids as long as they do not decompose the catalyst components under co-grinding conditions. It is also possible to treat the co-pulverized product with a solvent. There is no particular restriction on the temperature during co-pulverization, but it may be carried out at a temperature of 100 to 100°C, usually around room temperature.

Examples of solvents used during polymerization or the above treatment include saturated hydrocarbon compounds such as propane, pentane, hexane, heptane, octane, nonane, decane, cyclopentane, and cyclohexane, as well as aromatic ash such as benzene, toluene, and xylene. Hydrohydride compounds can also be used.

In the present invention, the organoaluminum and the stereoregularity improver in the formula C are aromatic hydrocarbons in which A and B are the same or different from each other, R is a hydrocarbon residue having 1 to 20 carbon atoms connecting B, Or compounds containing silicon, germanium, and tin,
X is a halogen atom or a hydrocarbon residue having 1 to 20 carbon atoms; 0M is a metal atom selected from Group 4.5 of the periodic table;)
It is characterized in that it is used in combination with an organic transition metal compound represented by

The organoaluminum used in the present invention has the general formula: A
An organoaluminum compound represented by lR3 is preferably used. Here R is halogen, oxygen, hydrogen, alkyl,
Represents a residue such as alkoxy or aryl, and each R may be the same or different, but at least one has an alkyl group, and 2 to 3 alkyl residues having from 12 carbon atoms are bonded. Trialkyl aluminum, dialkyl aluminum halide, etc. can be preferably used. Examples include trimethylaluminum, triethylaluminum, triisopropylaluminum, tributylaluminum, dimethylaluminum chloride, stylaluminum chloride, diisopropylaluminum chloride, ethylaluminum dichloride, and the like.

Examples of the organic transition metal compound used as a stereoregularity improver in the present invention include transition metal compounds having a group having conjugated π electrons as a ligand. or R-X2 (where A and B are the same or different aromatic hydrocarbons, R is a hydrocarbon residue having 1 to 20 carbon atoms connecting A and B, or a compound containing silicon, germanium, or tin) ,
χ is a halogen atom or a hydrocarbon residue having 1 to 20 carbon atoms. Gates are metal atoms selected from Group 4.5 of the periodic table. )
Compounds represented by can be preferably used.

In the general formula, A and B can be exemplified by monocyclic or polycyclic aromatic compounds having 5 to 30 carbon atoms. Specifically, in cyclopetadiene or a part thereof, all hydrogens have 1 to 1 carbon atoms. 10 substituted with an alkyl group (here, the alkyl group may have a structure in which its terminal end is bonded to the cyclopentadiene ring again), a polycyclic aromatic compound such as indene or fluorene, or a part of its hydrogen Alternatively, those substituted entirely with alkyl groups having 1 to 10 carbon atoms are exemplified.

R is preferably a dialkylmethylene group or a dialkylsilylene group, such as R'zC, R'2Si (in the formula R
"" represents hydrogen or an alkyl residue having 1 to 20 carbon atoms, and may be the same or different. ) can be preferably used, but further examples include ethylene groups represented by -CR'-CR'- (in the formula, R' is the same as above), where X is fluorine, chlorine, bromine, iodine , or methyl, ethyl,
Examples include alkyl groups such as propyl and butyl, and aromatic compounds such as cyclopentadienyl, with chlorine and methyl groups being particularly preferred.

In the present invention, the usage ratio of each of the above components varies depending on the compound used and the polymerization conditions, but usually 1 to 2000 mol of organic aluminum and 1 to 500 mol of organic transition metal compound used as stereoregularity improver per 1 mol of supported titanium. mole, the ratio of organic aluminum to the organic transition metal compound is 0.1 to 10,000 times by mole, usually 1 to 50 times
00 mole times.

In the present invention, α-olefins include ethylene, propylene, butene-1, pentene-1, hexene-1, heptene-1, octene-1, nonene-1, decene-1,
undecene-1, dodecene-1, tridecene-1, tetradecene-1, pentadecene-■, hexadecene-1,
In addition to linear α-olefins such as octadecene-1, 3-
Methylbutene-1,4-methylpentene-1,4,4-
Branched α-olefins such as dimethylpentene-1 are exemplified, and these α-olefins can be used for homopolymerization, copolymerization with each other, and, if necessary, copolymerization with dienes and the like.

Further, there are no particular limitations on the polymerization conditions, and solvent polymerization methods using an inert medium, bulk polymerization methods and gas phase polymerization methods in which substantially no inert medium is present can also be used. The polymerization temperature is -100 to 200° C1. The polymerization pressure is generally normal pressure to 100 kg/cdG. Preferably -100 to 100°C2 normal pressure to 50 kg/cdG.
It is.

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

Example I A) Production of supported transition metal catalyst A vibratory mill equipped with two crushing pounds each having an internal volume of 11 and containing 300 steel balls each having a diameter of 12 mm is prepared. 20 g of magnesium chloride and 4 grams of diisobutyl phthalate were added to this pot under a nitrogen atmosphere, and the mixture was pulverized for 17 hours. 300
- The above pulverized product Lo was placed in a round bottom flask under a nitrogen atmosphere.
After adding 100 g of titanium tetrachloride and stirring at 85°C for 2 hours, the supernatant liquid was removed by decantation. Furthermore, 100 d of titanium tetrachloride was added and the same operation was repeated. Next, add 200ml of n-hebutane and let it stand at room temperature.
After stirring for 5 minutes, the supernatant liquid was removed by decantation, which was repeated 7 times, and then 200 d of n-hebutane was added to obtain a carrier-type transition metal catalyst slurry. One part of this slurry was sampled and the titanium content was measured.
．． It contained 83wtχ.

B) Synthesis of organic transition metal compound As an organic transition metal catalyst component, isopropylcyclopentadienyl-1 fluorene synthesized according to a conventional method was lithiated with methyllithium, and zirconium tetrachloride was added for reaction.

Remove insoluble materials from the reaction mixture using a glass filter.
The solvent was removed by evaporation. Isopropyl (cyclopentadienyl-1-
Fluorenyl) zirconium dichloride was obtained. Similarly, ethylene bis-tetrahydroindenyl zirconium dichloride was obtained using ethylene bis-tetrahydroindene as a raw material.

C) Polymerization Thoroughly dried internal volume 3! 5US-30
0.17 g of triethylaluminum, 360 mg of the above organic transition metal compound, and 1001 g of the above supported transition metal catalyst in 1000+d of n-heptane in an autoclave manufactured by Co., Ltd.
A toluene solution in which these were mixed in this order was charged under a propylene atmosphere. Heat the contents of the autoclave and
After a few minutes, the internal temperature was raised to 40°C, and polymerization was continued for 2 hours while charging propylene to maintain the polymerization pressure at 5 kg/C4 gauge at 40°C. After the autoclave was cooled, unreacted propylene was purged and the contents were taken out and filtered to obtain 82.7 g of white powdery polypropylene.

The proportion of the boiling n-hebutane extraction residual polymer in this powdered polypropylene (hereinafter abbreviated as Powder II) is 95.
5χ, and the intrinsic viscosity number (hereinafter abbreviated as η, measured in a tetralin solution at 135°C) was 4.05.

Example 2 Polymerization of propylene was carried out in the same manner as in Example 1 except that 350 mg of ethylene bistetrahydroindenyl zirconium dichloride was used instead of isopropyl (cyclopentadienyl-1-fluorenyl) zirconium dichloride in Example 1. 104.6 g of white powdery polypropylene was obtained. Powder II of this powdered polypropylene had a 96.7χ and η of 4.35.

Example 3 A) Production of supported transition metal catalyst A vibratory mill equipped with two grinding pots each having an internal volume of 11 and containing 300 steel balls with a diameter of 12+u+ is prepared.

20g of magnesium chloride in the second pot under nitrogen atmosphere
, orthoethyl acetate 1 m, orthoethyl silicate IJd, 1
, 2-dichloroethane (3d) was added and the mixture was ground for 20 hours.

Add 10 g of the above pulverized product and 100 d of titanium tetrachloride to a 300+d round bottom flask under a nitrogen atmosphere, and heat at 85°C.
After stirring for 2 hours, the supernatant liquid was removed by decantation. Furthermore, 100 d of titanium tetrachloride was added and the same operation was repeated. Next, 200 ml of n-heptane was added, the mixture was stirred at room temperature for 15 minutes, and the supernatant liquid was removed by decantation, which was repeated 7 times. Next, 200 ml of n-heptane was added to form a carrier-type transition metal catalyst slurry. When a portion of this slurry was sampled and the titanium content was measured, it was found that the titanium content was 2.03 wtχ per gram of the carrier-type transition metal catalyst.

B) Polymerization Propylene was polymerized in the same manner as in Example 1 by charging 0.17 g of polymerized triethylaluminum, 350 mg of ethylene bistetrahydroindenyl zirconium dichloride as an organic transition metal compound, and 100 g of the above carrier-type transition metal catalyst in a propylene atmosphere. I did it. After cooling the autoclave, unreacted propylene is purged and the contents are taken out and filtered to obtain white powdered polypropylene 95.
．． 8g was obtained.

This powdered polypropylene powder 11 is 94.2χ
, η was 3.76.

〔Effect of the invention〕

By carrying out the method of the present invention, highly active and highly stereoregular polymers can be obtained and have high industrial value.

[Brief explanation of drawings]

FIG. 1 is a flow diagram to aid understanding of the present invention. Patent applicant Mitsui Toatsu Chemical Co., Ltd.

Claims (1)

[Claims] 1. In a method for polymerizing α-olefin using a solid catalyst consisting of a titanium compound supported on a magnesium compound, a stereoregularity improver, and a catalyst consisting of an organoaluminum, as the stereoregularity improver , General formula: ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (In the formula, A and B are the same or different aromatic hydrocarbons, and R connects A and B. A hydrocarbon residue having 1 to 20 carbon atoms, or a compound containing silicon, germanium, or tin,
X is a halogen atom or a hydrocarbon residue having 1 to 20 carbon atoms. M is a metal atom selected from Groups 4 and 5 of the periodic table. )
A method for polymerizing α-olefins, characterized by using an organic transition metal compound represented by: