JPH072796B2 - Transition metal catalyst component for olefin polymerization - Google Patents

Description

TECHNICAL FIELD The present invention relates to a catalyst component for olefin polymerization. Specifically, it relates to a transition metal catalyst component for olefin polymerization obtained by using crystalline magnesium halide having a specific X-ray diffraction line.

[Conventional technology]

For the polymerization of olefins, the use of a catalyst composed of a transition metal catalyst component comprising a titanium halide supported on a carrier such as magnesium halide and an organometallic compound is specified.
Since its disclosure in No. -12105, various improved methods have been proposed, and those having excellent performance are also known.

[Problems to be solved by the invention]

The above improving method is mainly to add a crusher to obtain a carrier and grind it, or dissolve magnesium halide used as a carrier in a solvent and then precipitate it to carry a transition metal and to form a catalyst for olefin polymerization. In this case, the carrier is treated so that the diffraction line measured by X-ray diffraction does not have a clear peak and is observed as a halo so that the carrier has excellent performance. In particular, the method of dissolving and then precipitating is excellent, and a highly active catalyst can be produced (for example, JP-A-56-11908). However, this method has a problem that a large amount of a precipitant is required and that a product having good activity cannot be obtained unless it is repeatedly treated with titanium halide. Further, it is difficult to provide a catalyst with excellent reproducibility and excellent performance by the method of adding additives and pulverizing.

The present inventor diligently studied a method for solving these problems, and by using a magnesium halide that gives a diffraction line of a specific crystallinity, conventionally, it is said that it cannot be used as it is as a carrier. The present invention has been completed by finding that even a carrier having a diffraction line is a catalyst component for olefin polymerization having a surprisingly excellent performance.

[Means for solving problems]

That is, the present invention has a maximum intensity near 7.38Å as a diffraction line measured by X-ray diffraction, and 7.93, 5.32, 3.57, 3.
A transition metal catalyst component for olefin polymerization that does not have a sharp diffraction line at least around 7.38Å obtained by treating crystalline MgBrCl with liquid titanium tetrachloride that gives a relatively strong diffraction line near 47, 3.26, 2.90Å. is there.

In the present invention, as the MgBrCl used as a carrier, its X-ray diffraction spectrum is at a specific place, that is, it has a maximum intensity in the vicinity of 7.38Å, 7.98, 5.32, 3.57, 3.26, 2.90Å
The manufacturing method is not particularly limited as long as it has a relatively strong diffraction line in the vicinity, but the following manufacturing method can be exemplified.

A Grignard reagent represented by the general formula R ¹ MgBr (wherein R ¹ is a hydrocarbon residue) (as well known, R ¹
It can be obtained by reacting a brominated hydrocarbon compound represented by Br with magnesium metal in the presence of ether or the like. ) And a chlorinated hydrocarbon compound represented by the general formula R ² Cl (wherein R ² is a hydrocarbon residue), the crystalline MgBrCl defined above can be easily obtained. The above-mentioned brominated hydrocarbon compound, the hydrocarbon residue of the chlorinated hydrocarbon compound may be any of aliphatic, alicyclic, aromatic hydrocarbon residues, etc., but is not particularly limited, It is common to use those having about 1 to 20 carbon atoms.

The reaction between the Grignard reagent and the chlorinated hydrocarbon proceeds sufficiently if it is carried out at the boiling point of the ether used as a medium. As the reaction proceeds, MgBrCl becomes insoluble and precipitates in the medium, and can be easily taken out by filtration or static separation.

The MgBrCl thus obtained is then treated with liquid titanium tetrachloride to form a transition metal catalyst component for olefin polymerization.

Here, the contact treatment is performed under mild conditions that do not apply a strong force to the particles of MgBrCl, for example, by simply dispersing MgBrCl in liquid titanium tetrachloride and stirring.
The temperature during the contact treatment is usually room temperature to 200 ° C.

Further, during the contact treatment, an electron donating compound such as an oxygen-containing organic compound such as ether, ester or alkoxysilane can be present.

The transition metal catalyst component of the present invention is a first to third group of the periodic table.
The olefin can be polymerized by using an organometallic compound of a group metal, such as organolithium, organosodium, organomagnesium, organoberium, or organoaluminum together.

The olefins that can be polymerized using the catalyst component of the present invention include ethylene, propylene, butene-1, pentene-1,
Hexene-1, octene-1, styrene, vinylnaphthalene, etc. are exemplified, and they are used for homopolymerization or mutual copolymerization thereof and further for copolymerization with diene.

In the present invention, the olefin polymerization can be carried out by a conventionally known olefin polymerization method, such as solution polymerization using a solvent, bulk polymerization using the olefin itself as a medium, or gas phase polymerization containing substantially no solvent.

〔Example〕

 Hereinafter, the present invention will be described with reference to examples.

Example 1 A 300 ml round bottom flask was charged with 7.4 g of magnesium and 20 ml of diethyl ether, and a mixture of 50 g of cyclohexane bromide and 50 ml of diethyl ether was added dropwise over 2 hours under reflux of ether. After that, the mixture is further stirred for 1 hour under reflux and C ₆ H
_A solution of ₁₁ MgBr in ethyl ether was prepared.

Then, 15 g of carbon tetrachloride was added under reflux of ethyl ether over 4 hours, and the mixture was further stirred under reflux for 2 hours.

Then, the mixture was filtered at room temperature, the solid content was washed with ethyl ether, and dried in a nitrogen gas stream to obtain a solid content of 40 g. The resulting solids were MgBrCl with Mg: Cl: Br approximately 1: 1: 1. The measurement results of X-ray diffraction are shown in FIG.

10 g of the above solid content was placed in a 200 ml round bottom flask, 50 ml of titanium tetrachloride and 50 ml of toluene were placed therein, and the mixture was stirred at 90 ° C. for 1 hour and then left to stand to remove the supernatant. Further, 50 ml of titanium tetrachloride and 50 ml of toluene were added, and the mixture was stirred at 90 ° C. for 1 hour, then left standing to remove the supernatant, and the obtained solid content was washed 7 times with toluene to obtain a transition metal catalyst component. .. As a result of the analysis, titanium was contained at 1.9 wt%.

Ethylene was polymerized using the transition metal catalyst component obtained by the above operation. N-Heptane 1 in autoclave with internal volume 2
Then, add 20 mg of the above transition metal catalyst component and 0.5 ml of triethylaluminum, add hydrogen to 2 kg / cm ² gauge, further add ethylene to 6 kg / cm ² gauge, then raise the temperature to 75 ° C., 10 kg / cm ² gauge Polymerization was carried out at 75 ° C. for 2 hours while adding ethylene so that Then, the mixture was cooled, unreacted ethylene was purged, and then filtered to obtain polyethylene powder. It was 360 g when dried and weighed. The intrinsic viscosity of this powder was 2.56 (measured with a tetralin solution at 135 ° C), the bulk specific gravity was 0.48, the particle size was 4.5% of fine powder of 200 mesh or less, and 0.3% of coarse particle of 10 mesh or more. The yield per Ti was 947 kg / g-Ti, the bulk specific gravity was good, and the particle size distribution was relatively sharp.

Example 2 10 g of MgBrCl obtained in Example 1 was placed in a 200 ml round bottom flask, 1.5 g of dibutyl phthalate, 50 ml of titanium tetrachloride and 10 ml of toluene were added, and the mixture was stirred at 120 ° C. for 1 hour to remove the supernatant. Next, 100 ml of titanium tetrachloride was added, and the mixture was stirred at 130 ° C. for 1 hour and left to stand to remove the supernatant, and the resulting solid content was n-
It was washed 9 times with hexane to obtain a transition metal catalyst component. As a result of the analysis, the titanium content was 2.6 wt%.

30 mg of the above transition metal catalyst component, triethylaluminum 0.
Polymerization was carried out in an autoclave of 5 using 15 ml and 0.03 ml of trimethoxyphenylsilane and using propylene itself as a solvent. At this time, add 1.5 kg of propylene and 3.2 NL of hydrogen, and add 75
Polymerization was carried out at 0 ° C for 2 hours. After polymerization for 2 hours, unreacted propylene was purged to obtain 670 g of polypropylene powder.
(22333 g / g of transition metal catalyst component) This powder had an intrinsic viscosity of 1.56 and a bulk specific gravity of 0.42 g / ml. The boiling n-heptane extraction residual ratio was 98.2%.

(Effect of the Invention) The catalyst of the present invention is excellent as a polyolefin polymerization catalyst component and is industrially valuable.

[Brief description of drawings]

FIG. 1 is a drawing showing an X-ray diffraction spectrum of magnesium halide used in producing the catalyst component of the present invention. FIG. 2 is a flow chart for facilitating the understanding of the present invention.

Claims (1)

[Claims] 1. Diffraction lines measured by X-ray diffraction
Has maximum strength near 7.38Å, 7.98, 5.32, 3.57, 3.47,
3.26, which gives a relatively strong diffraction line near 2.90Å
At least obtained by treating MgBrCl with liquid titanium tetrachloride.
7.38Å A transition metal catalyst component for olefin polymerization that has no sharp diffraction line near Å.