JPH0776248B2 - Olefin Polymerization Method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for polymerizing olefins. Specifically, it relates to a method for polymerizing olefins using a catalyst having a magnesium halide obtained by a specific method as a carrier.

[Conventional technology]

For the polymerization of olefins, it is recommended to use a catalyst composed of a transition metal catalyst component in which a titanium halide is supported on a carrier such as magnesium halide and an organometallic compound.
Since its disclosure in No. -12105, various improved methods have been proposed, and fairly excellent performances have been obtained.

[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.

[Means for solving problems]

The present inventors diligently studied a method for solving the above problems, found that magnesium halide which can be produced by a specific method is suitable as a carrier, and completed the present invention.

That is, the present invention has the general formula R ¹ MgX ¹ _L X ² _1-L (wherein R ¹ is a hydrocarbon residue, X ¹ is a bromine or iodine atom, X ² is a chlorine atom, and L is 0. <L <1.) And a Grignard reagent represented by the general formula R ² _n CX ² _4-n (wherein R ² is a hydrocarbon residue, X ² is a chlorine atom, and n is 0 ≦ n ≦ 3). MgX ¹ obtained by reaction with a chlorinated hydrocarbon compound represented by
_L X ² _2-L (in the formula, X ¹ is a bromine or iodine atom, X ² is a chlorine atom, and L is 0 <L <1) and titanium trichloride or titanium tetrachloride is supported. A method for polymerizing olefins is characterized by using a catalyst composed of the transition metal catalyst component thus obtained and an organoaluminum compound.

The present invention is characterized by a method for producing MgX ¹ _L X ² _2-L (wherein X ¹ is bromine or iodine, X ² is chlorine, and L is 0 <L <1) to be used as a carrier. There is no particular limitation on the method of supporting titanium trichloride or titanium tetrachloride on the obtained carrier, and various methods can be adopted. For example, the carrier may be a carboxylic acid ester, an ether, an orthoester, an alkoxy silicon, a phosphoric acid ester, an alcohol,
Contact or co-pulverize with oxygen-containing organic compounds such as ketones,
Then, a method of contact treatment with titanium trichloride or titanium tetrachloride or co-pulverization can be mentioned.

R ¹ MgX ¹ _L X used in producing magnesium halide represented by MgX ¹ _L X ² _2-L which is important in the present invention
^The Grignard reagent represented by 21 _-L (wherein R ¹ is a hydrocarbon residue, X ¹ is bromine or iodine, X ² is chlorine, and L is 0 <L <1) is known. In general, the halogenated hydrocarbon represented by R ¹ X ¹ and metallic magnesium are first reacted with a halogenated hydrocarbon in an amount of less than 1 mol with respect to metallic magnesium, and then the metal is formed. R ¹ X ² (wherein R ¹ is a hydrocarbon residue which may be the same as or different from R ¹ above, X ² is chlorine) is reacted so that the total amount of halogenated hydrocarbons relative to magnesium is 1 mol, It is fully aged and synthesized. As the solvent used here, ethers are usually used. The hydrocarbon residue may be any of aliphatic, alicyclic, aromatic hydrocarbon residues, etc., and is not particularly limited, but it may have 1 to 1 carbon atoms.
It is common to use about 20. ^One component used in producing MgX ¹ _L X ² _2-L is R ² _n CX ² _4-n (wherein R ² is a hydrocarbon residue, X ² is a chlorine atom, and n is 0 ≦ n ≦ 3. The above-mentioned hydrocarbon residue or hydrogen is exemplified as R ² , and the monochlorinated hydrocarbon, dichlorinated hydrocarbon and trichlorinated hydrocarbon are represented by In addition to hydrogen, carbon tetrachloride is also exemplified.

The reaction is carried out simply by adding a chlorinated hydrocarbon to the above Grignard reagent, and the reaction proceeds relatively easily, but when L is relatively small, the reaction may be carried out at a high temperature.

In the present invention, as the organoaluminum compound, trialkylaluminum such as triethylaluminum,
Examples thereof include dialkyl aluminum halides such as diethyl aluminum chloride.

Examples of the olefin used in the present invention include ethylene, propylene, butene-1, pentene-1, hexene-1, octene-1, styrene and vinylnaphthalene, and their homopolymerization or mutual copolymerization and further with diene. It is used for copolymerization.

In the present invention, the olefin polymerization can be applied by a conventional olefin polymerization method other than using the magnesium halide carrier produced by the above-mentioned method, such as solution polymerization using a solvent, bulk polymerization using the olefin itself as a medium, or solvent polymerization. Gas phase polymerization or the like, which is substantially free, may occur.

〔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 25 g of cyclohexane bromide and 50 ml of diethyl ether was added dropwise over 1 hour under reflux of ether. Then, 18 g of cyclohexane chloride was added over 1 hour, and the mixture was stirred under reflux for 2 hours, and C ₆ H ₁₁ MgBr _0.5
A solution of Cl _0.5 in diethyl ether was prepared.

Then allyl chloride 24 was added under reflux of diethyl ether.
What melt | dissolved g in 50 ml of diethyl ether was dripped over 3 hours, and also it stirred under reflux for 4 hours.

Then, the mixture was filtered at room temperature, the solid content was washed with diethyl ether, and dried with a nitrogen stream to obtain a solid content of 41 g. The obtained solid content was Mg: Cl: Br was approximately 1: 0.5: 1.5, and MgBr _0.5 Cl
It was _1.5 .

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, it contained 1.3 wt% of titanium.

Ethylene was polymerized using the transition metal catalyst component obtained by the above operation. N-heptane 1 in autoclave with internal volume 2
Placed, the transition metal catalyst component 20 mg, triethylaluminum 0.5ml added Hydrogenation until 2Kg / cm ² gauge, the temperature was further raised to ethylene 75 ° C. After the addition is-out 6 Kg / cm ² gauge, 10 Kg / cm ² Polymerization was carried out at 75 ° C. for 2 hours while adding ethylene so as to make a gauge. Then, the mixture was cooled, unreacted ethylene was purged, and then filtered to obtain polyethylene powder. It was 180 g when dried and weighed. The intrinsic viscosity of this powder was 2.65 (measured with a 135 ° C. tetralin solution), the bulk specific gravity was 0.39 g / ml, the particle size was 0.5% of fine powder of 200 mesh or less, and 0.0% of coarse particles of 10 mesh or more. Ti
The yield per unit was 692 Kg / g-Ti, the bulk specific gravity was good, and the particle size distribution was relatively sharp.

Example 2 Propylene was polymerized using the transition metal catalyst component obtained in Example 1. N-heptane 1 was put in the No. 2 autoclave, 30 mg of transition metal catalyst component, 0.32 ml of diethylaluminum chloride, 0.12 ml of methyl p-toluate, and 0.20 ml of triethylaluminum were added, and hydrogen of 0.1 kg / cm ² gauge,
Propylene was added at ² kg / cm ² gauge, then the internal temperature was adjusted to 70 ° C., and polymerization was performed at a total pressure of 6 kg / cm ² gauge for 2 hours. After completion of the polymerization, unreacted propylene was purged and the slurry was filtered to obtain 143 g of polypropylene powder, and 3.3 g of atactic polypropylene was obtained from the filtrate.

The polypropylene powder had a boiling n-heptane extraction residual rate of 96.8% (extracting 6 hours with boiling n-heptane using a Soxhlet extractor), an intrinsic viscosity of 2.12 and a bulk specific gravity of 0.39 g / ml.

Example 3 Magnesium halide having a composition of MgBr _0.3 Cl _1.7 was synthesized by changing the amounts of cyclohexane bromide and cyclohexane chloride used, and then 10 g was placed in a 200 ml round bottom flask.
Dibutyl phthalate 1.5g, titanium tetrachloride 50ml, toluene 10
ml was added and the mixture was stirred at 120 ° C. for 1 hour and the supernatant was removed. Next, 100 ml of titanium tetrachloride was added, and the mixture was stirred at 130 ° C. for 1 hour, allowed to stand, the supernatant was removed, and the obtained solid content was washed 9 times with n-hexane to obtain a transition metal catalyst component. As a result of the analysis, it contained 2.8 wt% titanium. This titanium catalyst 30m
Polypropylene powder (260 g) and n-heptane-soluble component (2.3 g) were obtained in the same manner as in Example 2, except that g, triethylaluminum (0.15 ml) and diphenyldimethoxysilane (0.03 ml) were used. The boiling n-heptane extraction residual rate of polypropylene powder was 98.9% (boiling n using a Soxhlet extractor).
-Extract for 6 hours with heptane) and the intrinsic viscosity is 2.25,
The bulk specific gravity was 0.45 g / ml.

〔The invention's effect〕

By carrying out the method of the present invention, it is possible to produce a polyolefin with high yield, which is industrially valuable.

[Brief description of drawings]

FIG. 1 is a flow chart for facilitating the understanding of the present invention.

Claims (1)

[Claims] 1. A general formula R ¹ MgX ¹ _L X ² _1-L (wherein R ¹ is a hydrocarbon residue, X ¹ is a bromine or iodine atom, X ² is a chlorine atom, and L is 0. <L <1.) And a Grignard reagent represented by the general formula R ² _n CX ² _4-n (wherein R ² is a hydrocarbon residue, X is
² is a chlorine atom, and n is an integer of 0 ≦ n ≦ 3. ) MgX ¹ _L X ² obtained by reaction with a chlorinated hydrocarbon compound represented by
_2-L (in the formula, X ¹ is a bromine or iodine atom, X ² is a chlorine atom, and L is 0 <L <1) and titanium trichloride or titanium tetrachloride is supported. A method for polymerizing an olefin, which comprises using a catalyst comprising a transition metal catalyst component and an organoaluminum compound.