JPS582305A - Polymerization of ethylene - Google Patents

Abstract

PURPOSE:A catalyst which is prepared by reaction of a product from Al halide and a specific organosilicon compound with a Grignard reagent, followed by treatment with a Ti compound and combination of the product with an organoaluminum compound is used to effect polymerization to produce to the titled polymer of high bulk density without deashing process. CONSTITUTION:A reaction product from (A) an aluminum halide of AlX3<1> (X<1> is Cl, Br, I) and (B) an organosilicon compound of Rn<1>Si(OR<2>)4-n(R<1>, R<2> are 1-8C hydrocarbon; n is 0, 1, 2, 3) such as tetramethoxysilane is made to react with (C) a Grignard reagent of R<3>MgX<2> (R<3> is 1-8C alkyl; X<2> is halogen), then the product is treated in order with titanium tetrahalide, organosilicon compound and titanium tetrahalide to give the solid catalyst component. The solid component is combined with (D) an organoaluminum compound of AlR3<4> (R<4> is 2-6C alkyl) and the resultant catalyst is used to effect the polymerization of ethylene.

Description

[Detailed description of the invention] This invention relates to a method for polymerizing ethylene.

By polymerizing ethylene in the presence of a highly active polymerization catalyst obtained from a solid catalyst component in which titanium tetrahalide is supported on a magnesium compound and an organoaluminum compound, an operation for removing catalyst residue from the resulting polymer can be omitted. Many proposals have been made regarding ways to increase the polymer yield per titanium.

For example, Tokukai Showa 5! In Publication No. 1-78287.

In the presence of a catalyst obtained from a solid catalyst component obtained by reacting a reaction product of aluminum halide and tetraalkoxysilane with magnesium alcoholade and contacting the resulting solid with titanium tetrahalide and an organoaluminum compound. discloses a method for polymerizing ethylene. Furthermore, in the above publication, the ethylene pressure during double polymerization is i
It has been shown that the polymer yield per hour of polymerization time per titanium 17 is approximately 7 s 1 kg when expressed as oKg/i. In order to omit the operation of removing catalyst residues from the produced polyethylene, it is desirable to further increase the polymer yield per titanium.

The present invention provides a method for polymerizing ethylene with a significantly high polymer yield per titanium unit.

In other words, this invention.

Represented by the formula AtXA[I] (in the formula, xl represents a chlorine atom, a bromine atom, or an iodine atom)...aluminum halogenide
゛Formula R1n5i(OR2)4-n CII〕(
In the formula, ul and R2 each represent an alkyl group having 1 to 8 carbon atoms or a phenyl group, and n is 0°1.2 or 6. ) to the reaction product with an organosilicon compound.

Formula R3MgX2CIII (In the formula, R3 represents an alkyl group having 1 to 8 carbon atoms.

X2 represents a rogen atom. ,), the resulting solid is brought into contact with titanium tetrachloride, the resulting titanium-containing solid is treated with an organosilicon compound represented by the above formula [■], and then the treated solid is A solid catalyst component obtained by contacting tetra... with titanium rogenide.

Ethylene is polymerized in the presence of a catalyst obtained from an organoaluminum compound represented by the formula had [IV:] (wherein R4 represents an alkyl group having 2 to 6 carbon atoms) This is a polymerization method.

According to this invention, since the polymer yield per titanium unit is extremely large, there is no need to remove catalyst residues from the produced polymer, and the produced polymer has an excellent bulk specific gravity.

In this invention, the solid catalyst component is prepared using a substantially anhydrous compound under an inert gas atmosphere such as nitrogen or argon.

Specific examples of the aluminum halide represented by formula [I] include aluminum chloride, aluminum bromide, and aluminum iodide, among which aluminum chloride is preferably used.

Specific examples of the organosilicon compound coated with formula [11] include tetramethoquinosilane, tetraethoxysilane,
Tetrabutoxysilane, tetrapentoxysilane, methyltrimethoxysilane/, methyltriethoxysilane, methyltri-n-butoxysilane, methyltriisopentoxysilane, methyltri-n-hexoxysilane, methyltriisooctoxysilane, ethyltriethoxy Silane.

Ethyltriynepropoxysilane, ethyltriisopentoxysilane, n-butyltriethoxysilane, inobutyltriethoxysilane, isopentyltriethoxysilane, isopentyltri-n-butoxysilane, dimethyljethoxysilane.

Dimethyldi-n-butoxysilane, dimethyldiisopentoxysilane, diethyljethoxysilane.

diethyldiisopentoxysilane, di-n-butyljethoxysilane, diisobutyldiisobentoxysilane,
Trimethylmethoxysilane, trimethylethoxy7rane, trimethylisobutoxysilane, triethylisoprobogysilane, tri-n-propylethoxysilane, tri-n-butyloxysilane, triisopentylethoxy7rane, phenyltriethoxysilane , phenyltriinbutoxysilane, phenyltriisopentoxysilane, diphenyljethoxysilane, diphenyldiisobenxoxysilane, diphenyldioctoxysilane,
Triphenylmethoxysilane, triphenylethoxysilane, triphenylisopentoxysilane, trimethylphenoxysilane.

Triethylphenoxysilane, dimethyldiphenoxy 7
Examples include orchids.

What is the proportion of aluminum halide used in the reaction?

0.25 to 1.0 mol per mol of organosilicon compound.

In particular, it is preferably 0.5 to 2 mol.

...The reaction between aluminum halogenide and an organosilicon compound is usually carried out using both compounds in an inert organic solvent.

This is carried out by stirring for 0.1 to 2 hours at a temperature in the range -50 to 100°C. The reaction proceeds exothermically and the two reaction products are obtained as an inert organic solvent bath solution. The reaction product can be subjected to the reaction with a Grignard compound as the above '#Ig without being isolated.

Among the Grignard compounds represented by the formula [■],
庺：Argylmagnesium chloride, which is a chlorine atom, is preferably used, and a specific example thereof is.

Examples include methylmagnesium chloride, ethylmagnesium chloride, n-butylmagnesium chloride, and n-butylmagnesium chloride.

The amount of Grignard compound used is per mole of organosilicon compound used to prepare one reaction product.

It is preferably 0.05 to 4 mol, particularly 1.5 to 2 mol.

There is no particular restriction on the method of reacting the reaction product and the Grignard compound, but it is possible to add the Grignard compound in an ether bath or a mixed solvent solution of ether and an aromatic hydrocarbon to the inert organic solvent bath solution of the two reaction products. It is convenient to carry out the addition in stages, even in the reverse order. ”As for the ether in the second book.

Compounds represented by the formula R5-0-R6 (wherein R5 and R6 represent an alkyl group having 2 to 8 carbon atoms) are preferably used, and specific examples include diethyl ether, diisonolopyl ether, Examples include -b, diamyl ether, diynamyl ether, and the like.

Reaction temperature d, usually -50 to 100°C2, preferably -2
0-25°C. There is no particular restriction on the reaction time, but it is usually 5 minutes or more. As the reaction progresses, a white solid precipitates out. The solid thus obtained is washed with an inert organic solvent and then brought into contact with titanium tetrahalide.

Specific examples of titanium tetrachloride in this invention include titanium tetrachloride, titanium tetrabromide, and titanium tetraiodide, of which titanium tetrachloride is preferably used.

The number of titanium tetrahalides used is at least 1 mol, especially 2 mol, per mol of Grignard compound used during the preparation of the solid.
It is preferable that it is 100 mol.

The solid and the titanium tetralogenide can be brought into contact in the presence T1 or absence of an inert organic solvent. The temperature during contact is 20 to 200°C, especially 60 to 140°C.
Preferably, the temperature is °C. There is no particular restriction on the contact time, but it is usually 0.5 to 1 hour.

The titanium-containing solid is separated from the thus obtained mixture containing the titanium-containing solid by filtration, decanting, etc., and washed with an inert organic solvent if necessary.

It is subjected to treatment with an organosilicon compound represented by the above formula [■].

Among the organosilicon compounds represented by formula CII), trialkylphenoxysilane is preferably used.

The usage ratio of the organosilicon compound is 0.5 to 0.5 to the solid.
Preferably it is 20% by weight, especially 1 to 15% by weight.

There are no particular restrictions on the method of treating the titanium-containing solid with an organosilicon compound, but the method of treating the titanium-containing solid with an inert organic solvent is not particularly limited. Conveniently, a method is employed in which the suspension is made cloudy, an organosilicon compound is added to this suspension, and the mixture is stirred. The treatment temperature is preferably 0 to 200°C, particularly 5 to 150°C. There is no particular limit on the processing time, but it is usually 25
It's more than a minute.

The mixture containing the treated solid obtained in this way can be used as is, or the treated solid can be filtered from this mixture.

After fractionating by tilting or the like and washing with an inert organic solvent if necessary, it is brought into contact with the titanium halide again.

The contact between the treated solid and the titanium tetrahalide can be carried out in the same manner as the contact between the titanium tetrahalide and the solid obtained by reacting the reaction product and the Grignard compound.

The solid catalyst component is separated from the mixture containing the solid catalyst component thus obtained by filtration, decanting, etc.

Wash with inert organic solvent. The solid catalyst component contains titanium in a proportion of 0.5 to 10% by weight of gold.

Inert organic solvents used in each step of preparing the solid catalyst component include aliphatic hydrocarbons such as hexane and heflin;
Examples include aromatic hydrocarbons such as toluene, benzene, and xylene, and halides of these hydrocarbons.

In this invention, ethylene is polymerized in the presence of a catalyst obtained from a solid catalyst component and an organoaluminum compound represented by formula [IV].

Specific examples of the organoaluminum compound represented by formula [IV) include triethylaluminum, triisobutylaluminum, and tri-n-hexylaluminum, among which triethylaluminum and triisobutylaluminum are preferably used.

The amount of organoaluminum compound used is usually 1 to 1.000 moles per gram atom of titanium in the solid catalyst component.

The polymerization reaction of ethylene can be carried out in a liquid phase or a gas phase.

When carrying out a polymerization reaction in a liquid phase, examples of dual polymerization solvents include n-butane, n-propane + n-hexane, n-
Aliphatic hydrocarbons such as heptane.

Alicyclic hydrocarbons such as cyclohexane and cyclopentane, and aromatic hydrocarbons such as benzene and toluene are used. There is no particular restriction on the catalyst concentration in the polymerization solvent, but in general, for the solid catalyst component, it is 0.0005 to 10 milligram atoms calculated as titanium metal per 1 polymerization solvent, and for trialkylaluminum, it is 0.0005 to 10 milligram atoms per 1 polymerization solvent. It is 0.001 to 1.000 mmol.

In this invention, not only ethylene is polymerized alone, but also ethylene and α-olenin having 6 or more carbon atoms, such as propylene and 1-butene.

4-methyl-1-pentene and 1-hexene can be copolymerized.

In the present invention, the bipolymerization reaction is carried out in a state substantially free of moisture and oxygen, similar to the usual polymerization reaction of ethylene using a Ziegler type catalyst.

The polymerization temperature is usually 39 to 100°C, and the double polymerization pressure is usually 1 to soK.

In this invention, the molecular weight of the ethylene polymer obtained can be easily adjusted by adding hydrogen to the monopolymerization system.

Next, examples will be shown. In the description below.

"Polymerization activity" refers to the polymer yield per hour of polymerization time per 12 titanium in the solid catalyst component used in the bipolymerization reaction (
1M, d is the melt flow index measured at 190°C under a load of 2.16 Ky/- according to AsTMDi, 238.

In the examples, all solid catalyst components were prepared in a dry nitrogen gas atmosphere.

Example 1 (1) Preparation of solid catalyst component 15 mmol of anhydrous aluminum chloride and 30 ml of toluene
was added thereto, and 10 ml of a toluene solution containing 15 mmol of phenyltriethoxysilane was added dropwise at 25°C over 30 minutes while stirring, followed by reaction at the same temperature for 60 minutes.

The reaction mixture was cooled to -6°C under stirring.

18 rttl of diisoamyl ether containing 27 mmol of n-butylmagnesium chloride was added dropwise to the reaction product mixture over a period of 3 o'clock, and then the temperature was raised to 60°C over 60 minutes, and the temperature was maintained at the same temperature for 60 minutes for reaction.

The precipitated solid (4,2y) was separated and filtered with toluene.
Washed 5 times with e.

The solid was suspended in 30 ml of toluene, 16.5 ml of titanium tetrachloride was added to this suspension, and the mixture was heated at 90'C for 60 hours with stirring.
The solid was contacted with titanium tetrachloride for a minute.

At the same temperature, titanium-containing solids were separated into n-hebutane 301
It was washed twice with 1 Ll and then twice with 30 ml of toluene.

Suspend the titanium-containing solid in 60°C of toluene.

Trimethylphenoxysilane 0.422 (
10% by weight based on solids) and heated to 90°C with stirring for 6 hours.
It was held for 0 minutes. The treated solid was separated at the same temperature and washed twice with 30 m# of n-hebutane and twice with 3 m# of toluene.

The treated solid was suspended in 30 m# of toluene, 16.5 ml of titanium tetrachloride was added to this suspension, and the treated body was brought into contact with the titanium tetrachloride at 90°C for 60 minutes while stirring. The obtained solid catalyst component was washed 5 times with 0 ml of n-hegetane at the same temperature, and then 100 m/ml of rn-hebutane was added to prepare a suspension of the solid catalyst component. The titanium content of the solid catalyst component was 5.87% by weight.

(2) Polymerization After a glass ampoule containing a suspension of a solid catalyst component (omg as a solid catalyst component) was attached to an autoclave with an internal volume of 2 tons and equipped with a stirrer, the air in the autoclave was replaced with nitrogen.

1 t/t of n-hexane and then 1.5 m/t of n-hexane containing 300 moles of triethylaluminum per gram atom of titanium in the solid catalyst component,
The autoclave contents were heated to 90°C. At this time, the internal pressure of the autoclave (gauge pressure, the same applies hereinafter) is O-
It was 9Kg/crA.

After introducing ethylene into the autoclave at a total pressure of y and 91g7CrA, stirring was started to crush the glass ampoule, and ethylene was polymerized at 90°C for 60 minutes.

During the polymerization, ethylene was continuously fed and the total pressure was kept at 7. qKg/
I kept it on my shoulder.

After the polymerization reaction was completed, unreacted ethylene was released, and the polymer was separated and dried under reduced pressure at 50°C for 20 hours.

White polyethylene 239.5f/(4j. Polymerization activity is 1360. Density is o, q45y/shoulder, bulk ratio is 0.
It was 40.

Examples 2 and 3 Example 1 was repeated except that the number of moles of triethylaluminum used per gram atom of titanium in the solid catalyst component (hereinafter referred to as At/T1 ratio) was changed as shown in Table 1.

The results are shown in Table 1.

Table 1 Examples 4 to 6 Prior to introducing ethylene, hydrogen was introduced until the hydrogen pressure as listed in Table 2 was reached, and then the ethylene pressure was increased to 7 kg/-.
Example 1 was repeated except that ethylene was introduced continuously so that the total pressure was maintained at the initial total pressure during the polymerization reaction. The results are shown in Table 2.

Table 2 Examples 7 to 9 Example 1 was repeated, except that 15 mmol of the compound listed in Table 3 was used instead of phenyltriethoxysilane as the organosilicon compound to be reacted with anhydrous aluminum chloride. Table 3 shows the titanium content of the solid catalyst component and the polymerization results.

Table 3 Examples 10 to 14 Predetermined amounts of the compounds listed in Table 4 in place of trimethylphenoxysilane as organosilicon compounds for treating titanium-containing solids (the amounts used in Table 4 are by weight relative to the solid) Example 1 was repeated except that . Table 4 shows the titanium content of the solid catalyst component and the polymerization results.

TABLE 4 Examples 15-17 Example 1 is repeated except that the amount of phenyltriethoxysilane used (expressed in weight percent of solids) to treat the titanium-containing solids was varied as described in Table 5. Table 5 shows the titanium content of the solid catalyst component and the polymerization results.

Table 5 Examples 18 to 20 A suspension of the solid catalyst prepared in Example 1 (1 ton as solid catalyst component) was placed in an autoclave equipped with a stirrer and having an internal volume of 1 t.
．． After attaching the glass ampoule containing 657IIg), the air in the autoclave was replaced with nitrogen.

2 ml of n-hebutane containing triethylaluminum in an amount to give an At/T1 ratio of 300 plus hydrogen were introduced into the autoclave until a predetermined pressure was reached.

Thereafter, predetermined amounts of liquid butene-1: and liquid n-butane were pressurized into the autoclave. The autoclave contents were heated to 66°C, and then ethylene was introduced into the autoclave until the predetermined ethylene pressure was reached (total pressure: 28°C).
K, g/aΔ), stirring was started, the glass ampoule was crushed, and ethylene and butene-1 were copolymerized at 66°C for 60 minutes. Polymerization in progress.

Ethylene was continuously fed and the total pressure was maintained at 28 Kg/i.

After the polymerization reaction is completed, unreacted monomers and n-butane are released, and the resulting ethylene-butene-1 copolymer is
It was dried under reduced pressure at 0°C for 20 hours. The polymerization results are shown in Table 6.

Chapter 6 Table

Claims (1)

[Scope of Claims] Aluminum halide represented by the formula AtXj[r) (wherein xi represents a chlorine atom, a bromine atom, or an iodine atom) and the formula R'n5i(OR2)4-n (II ) (formula In the reaction product with an organosilicon compound, R1 and R2 each represent an alkyl group having 1 to 8 carbon atoms, which represents a phenyl group, and where n is 0.1.2. Formula R3MgX”(l[) (In the formula, RB has 1 carbon number
It represents an alkyl group of ~8, and x2 represents...a rogen atom. ), the resulting solid is brought into contact with titanium chloride, the resulting titanium-containing solid is treated with an organosilicon compound represented by the above formula [■], and then the treated solid is A solid catalyst component obtained by contacting with titanium halide. Formula AtR'3 CIV] (in the formula, n4 is the number of carbon atoms
~6 alkyl group is shown. ) A method for polymerizing ethylene, which comprises polymerizing ethylene in the presence of a catalyst obtained from an organoaluminum compound represented by: