JPH0680092B2 - Method for preparing catalyst component for olefin polymerization - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for preparing a solid transition metal component of a Ziegler type catalyst for olefin polymerization. More specifically, the present invention relates to a method of preparing a supported catalyst component that has important features in the components used and their mode of preparation.

Prior art and its problems When an olefin having 3 or more carbon atoms is polymerized using a catalyst component in which a titanium compound as a transition metal component of a Ziegler type catalyst is supported on a magnesium compound, the catalyst has high activity. It is known that a polyolefin can be obtained in a correspondingly high yield, and it is also known that a polyolefin having excellent stereoregularity can be obtained by using a catalyst supporting a titanium compound by a specific method, Many inventions have been proposed. The present inventors have also found that the catalyst component (A) composed of the catalyst product of the specific components (A ₁ ) to (A ₃ ).
(Detailed below) is proposed.

By the way, such a catalyst component is a solid, but since it is necessary to use a liquid raw material and to make good contact with the solid carrier raw material, its preparation is usually performed in a slurry state. Also, the prepared catalyst component preparation is often in the form of a slurry.

Needless to say, such a catalyst component slurry must exhibit the desired catalytic activity to the maximum extent, but according to the experience of the present inventors, if the preparation method is not suitable, the catalytic activity and the polymer can be reduced. Decrease in catalyst performance such as properties is observed, and deterioration of the prepared catalyst component over time (during storage) is observed.

In particular, deterioration of the prepared catalyst component slurry over time is a very serious problem in production on a plant scale. This is because stable operation is of the utmost importance in plant production, and for that purpose it is necessary that the catalyst used is stable for a long period of time during holding.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a solution to the above point, and to achieve this object by preparing a specific catalyst component in a high-concentration slurry state.

Therefore, the method for preparing the catalyst component for olefin polymerization comprising the solid component (A) according to the present invention comprises obtaining the following catalyst component (A) as a slurry in an inert solvent, at which time the slurry concentration is adjusted to 5 g of the catalyst component. (A) / liter inert solvent or more.

Catalyst component (A) A contact product of the following component (A ₁ ), component (A ₂ ) and component (A ₃ ).

Component (A ₁ ) magnesium dihalide, titanium tetraalkoxide and / or polymer thereof, and general formula A contact product of a polymer silicon compound having a structure represented by (R ¹ is a hydrocarbon residue).

Ingredient (A ₂ ) Aromatic carboxylic acid ester Ingredient (A ₃ ) At least one of the following ingredients (a) and (b) (provided that the amount of ingredient (a) and ingredient (b) used is that of ingredient (A ₁ A) in the atomic ratio of 0.1 to 10 with respect to the magnesium compound)).

(A) A compound represented by the general formula TiX ₄ (where X is halogen), (b) A compound represented by the general formula SiX ₄ (where X is a halogen).

Effects When the catalyst component is prepared by the method of the present invention, it can be used without deteriorating the catalyst performance. In particular, when the catalyst component is held for a long time, it can be used with stable performance without deterioration over time. For example, it can be used stably for one week or one month. As mentioned above, this is extremely important in production on a plant scale.

The catalyst component according to the present invention has its own characteristic, and due to this characteristic, a highly stereoregular polyolefin can be obtained in high yield due to this characteristic.

DETAILED DESCRIPTION OF THE INVENTION Solid Component (A) This is a contact product of the following components (A ₁ ), (A ₂ ), and (A ₃ ).

1) Component (A ₁ ) (1) Composition The component (A ₁ ) is a solid composition composed of magnesium dihalide, titanium tetraalkoxide and / or its polymer, and a specific polymer silicon compound.

This solid composition (A ₁ ) is not a complex of magnesium dihalide and titanium tetraalkoxide and / or its polymer and a polymeric silicon compound, but is another solid. At present, its content has not been fully analyzed,
According to the result of the composition analysis, this solid composition contains titanium, magnesium, halogen and silicon.

The component (A ₁ ) contains the above three components as essential components, but may contain an auxiliary component, if necessary, as long as the gist of the present invention is not impaired. Therefore, the component (A ₁ ) can contain an alcohol and / or an organic acid ester with respect to the magnesium dihalide constituting the component (A ₁ ).

(2) Production Component (A ₁ ) is produced by mutual contact of magnesium dihalide, titanium tetraalkoxide and / or its polymer, and a polymeric silicon compound (and alcohol or ester).

(A) Magnesium dihalide For example, there are MgF ₂ , MgCl ₂ , MgBr ₂ , and the like.

(B) Titanium tetraalkoxide and its polymer As titanium tetraalkoxide, for example, Ti (OC
_{2 H 5) 4, Ti (} O-isoC 3 H 7) 4, Ti (O-nC 4 H 9) 4, Ti (O-nC 3 H 7) 4, Ti (O-isoC 4 H 9) 4, Ti ([OCH ₂ CH (CH _{3) 2] 4,} Ti [OC (CH _{3) 3] 4, Ti (O-nC 5} H 11) 4, Ti (O-nC 6 H 13) 4, Ti (O -nC ₇ H _{15) 4,} Ti _{[OCH 2 CH (C 2 H 5} ) C 4 H 9 ] _4, and the like. preferred among _{these, Ti (O 2 H 5)} 4 and Ti (O -nC ₄ H _{9) 4,} a.

Polymers of titanium tetraalkoxide include those represented by the following formula.

Here, R _{2 to} R ₅ are the same or different hydrocarbon residues, preferably an aliphatic or aromatic hydrocarbon having 1 to 10 carbon atoms, particularly an aliphatic hydrocarbon having 2 to 6 carbon atoms. n is a number of 2 or more, particularly up to 20. It is desirable that the value of n be selected so that the polytitanate can be used as it is or as a solution in liquid form for the step of contacting with other components. The value n that is suitable for handling is about 2 to 14, preferably about 2 to 10. Specific examples of such polytitanate include normal butyl polytitanate (n = 2 to
10), hexyl polytitanate (n = 2 to 10), normal octyl polytitanate (n = 2 to 10), and the like.
Of these, normal butyl polytitanate is preferred.

(C) Polymer Silicon Compound Those represented by the following formula are suitable.

formula R is a hydrocarbon residue having 1 to 10 carbon atoms, particularly 1 to 6 carbon atoms.

Specific examples of the polymer silicon compound having such a structural unit include methylhydropolysiloxane, ethylhydropolysiloxane, phenylhydropolysiloxane,
Examples thereof include cyclohexylhydropolysiloxane.

The degree of polymerization in this case is not particularly limited,
Considering handling, the viscosity is 10 centistokes to 10
It is preferably about 0 centistokes. Also,
The terminal structure of the hydropolysiloxane does not have a great influence, but is preferably blocked with an inert group such as a trialkylsilyl group.

(D) Contact of Each Component (Amount Ratio) The amount of each component used may be arbitrary as long as the effects of the present invention are recognized, but generally, the following range is preferable.

The amount of titanium tetraalkoxide and / or its polymer to be used is preferably in the range of 0.1 to 10 and more preferably in the range of 1 to 4, more preferably 2 in terms of molar ratio with respect to the magnesium dihalide. Within the range of ~ 3.

The amount of the polymeric silicon compound used is preferably in the range of 1 × 10 ^{−2 to} 100, preferably in the range of 0.1 to 10, and more preferably in the range of 1 to 4 in terms of molar ratio with respect to magnesium dihalide. It is within the range.

When alcohol and / or organic acid ester is used, the amount thereof is within the range of 1 × 10 ^{−3 to} 5 × 10 ^{−1 in} molar ratio with respect to the magnesium dihalide.

(Contact Method) The solid component (A ₁ ) of the present invention is obtained by contacting the above-mentioned three components. The contact of the three components can be performed by any generally known method. Generally, −100
The contact may be performed within a temperature range of ℃ to 200 ℃. The contact time is usually about 10 minutes to 20 hours.

The contact of the three components is preferably carried out with stirring, and it is also possible to carry out the contact by mechanical pulverization with a ball mill, a vibration mill, or the like. The order of contact of the three components is
It may be any as long as the effect of the present invention is recognized, but it is produced by contacting magnesium dihalide with titanium tetraalkoxide, and alcohol or organic acid ester to dissolve magnesium dihalide, and then contacting with polymer silicon compound. It is common to deposit a substance. The contact of the three components can also be performed in the presence of a dispersion medium. Examples of the dispersion medium in that case include hydrocarbons, halogenated hydrocarbons, dialkyl siloxanes and the like. Specific examples of hydrocarbons include hexane, heptane, toluene, cyclohexane, etc. Specific examples of halogenated hydrocarbons include n-butyl chloride, 1,2-dichloroethylene, carbon tetrachloride, chlorobenzene, etc. Specific examples of the siloxane include dimethylpolysiloxane and methyl-phenylpolysiloxane.

2) Component (A ₂ ) Component (A ₂ ) is an aromatic carboxylic acid ester.

What is usually used as the aromatic carboxylic acid ester is, for example, a carboxylic acid ester derived from an aromatic mono- or dicarboxylic acid having 7 to 12 carbon atoms and an alcohol having 1 to 12 carbon atoms. Specifically, methyl benzoate, ethyl benzoate, methyl toluate, ethyl toluate, ethyl anisate, diethyl phthalate, di-n-butyl phthalate, di-n-heptyl phthalate, di-n-butyl terephthalate, Examples include diethyl terephthalate and diisobutyl phthalate.

Specific examples of the silicon alkoxide-containing compound include monophenyltrimethoxysilane, diphenyldimethoxysilane, tetraethoxysilane, monophenyltriethoxysilane, diphenyldiethoxysilane, methyltrimethoxysilane, dimethyldiethoxysilane, and methylphenyldimethoxysilane. , Etc.

3) the component (A ₃₎ which is at least one of the following components (a) ~ (b).

(A) A compound represented by the general formula TiX ₄ (where X is a halogen). Specific examples include TiCl ₄ and TiBr ₄ . Of these, TiCl _{4 and the} like are preferable.

(B) A compound represented by the general formula SiX ₄ (where X is a halogen). Specific examples include SiCl ₄ and SiBr ₄ . Of these, SiCl _{4 and the} like are preferable.

Preparation The present invention catalyst component of the present invention the catalyst component (A) is a contact product of the component _{(A 1) ~ (A 3} ). And this invention prepares this as a high concentration slurry.

1) Amount Ratio The amount of each component used is arbitrary as long as the effects of the present invention are observed, but generally, the following ranges are preferable.

The amount of the component (A ₂ ) used is preferably in the range of 1 × 10 ⁻³ to 10 with respect to the magnesium dihalide constituting the component (A ₁ ), preferably 1 × 10 ⁻² to 1. It is within the range.

The amount of the component as the component (A ₃₎ (a) and component (b), respectively, in the range of 0.1 to 10 in atomic ratio to the magnesium compound constituting the component (A _1).

2) Contact Method The catalyst component of the present invention is obtained by contacting the above-mentioned component (A ₁ ) with the component (A ₂ ) and the component (A ₃ ).
The contact may be generally performed within a temperature range of -100 ° C to 200 ° C.

The contact time is usually about 10 minutes to 20 hours.

The solid component (A ₁ ) and the components (A ₂ ) to (A ₃ ) are preferably contacted with stirring, and a ball mill, a vibration mill,
It is also possible to bring them into contact with each other by mechanically pulverizing them. The order of contact is as long as the effect of the present invention is recognized.
It can be arbitrary.

The contact between the solid component (A ₁ ) and the components (A ₂ ) to (A ₃ ) can be carried out in the presence of a dispersion medium. The dispersion medium at that time can be selected from those exemplified as those to be used when producing the component (A ₁ ).

3) Diluting method with an inert solvent As the diluting method with an inert solvent, any conventionally known method is sufficient. Examples of the inert solvent include hydrocarbons and halogenated hydrocarbons. As a specific example,
Hexane, heptane, toluene, cyclohexane, kerosene, n-butyl chloride, 1,2 dichloroethylene, carbon tetrachloride, chlorobenzene and the like can be mentioned. The dilution is preferably performed in an inert gas atmosphere. The temperature at the time of dilution is usually about 0 ° C to 100 ° C, preferably 0 ° C to 50 ° C.
It is about ℃. The inert solvent used is preferably dehydrated and deoxygenated sufficiently.

The concentration of this chiller is according to the invention 5 g of catalyst component (A).
Per liter of inert solvent or more, but usually 5 to 100 g / liter, preferably 10 to 50 g / liter,
Is.

A slurry concentration of at least 5 g catalyst component (A) / liter inert solvent is applied throughout the storage period after the produced catalyst component (A) has been prepared and before it is subjected to polymerization.

Polymerization of Olefin 1) Formation of Catalyst The catalyst component of the present invention can be used for the polymerization of olefin in combination with an organometallic compound that is a cocatalyst. Any of the organometallic compounds of metals of Groups I-IV of the Periodic Table known as cocatalysts can be used. In particular, organic aluminum compounds are preferable. Specific examples of the organoaluminum compound are represented by the general formula: ▲ R ³ _3-n ▼ AlXn or R _3- mAl (OR ⁵ ) m (wherein R ³ , R ⁴ and R ⁵ are the same or different carbons). A hydrocarbon residue of about several 1 to 20 or hydrogen, X is halogen, and n and m are 0 ≦ n ≦ 2 and 0 ≦ m ≦ 1 respectively.). Specifically, there are the following.

(A) Trialkylaluminum such as trimethylaluminum, triethylaluminum, triisobutylaluminum, trihexylaluminum, trioctylaluminum, tridecylaluminum, etc., (b) diethylaluminum monochloride, diisobutylaluminum monochloride, ethylaluminum sesquichloride, ethyl Alkyl aluminum halides such as aluminum dichloride, (c) diethyl aluminum hydride, dialkyl aluminum hydride such as diisobutyl aluminum hydride, (d) diethyl aluminum ethoxide, diethyl aluminum butoxide, alkyl aluminum alkoxide such as diethyl aluminum phenoxide, and the like. .

In addition to these organoaluminum compounds (a) to (c), other organometallic compounds such as ▲ R ⁷ _3-a ▼ Al (OR ⁸ ) a (1≤a≤3, R ⁷ and R ⁸ are the same or different. It may also be an alkylaluminum alkoxide represented by a hydrocarbon residue having about 1 to 20 carbon atoms.). For example, combined use of triethyl aluminum and diethyl aluminum ethoxide, combined use of diethyl aluminum monochloride and diethyl aluminum ethoxide, combined use of ethyl aluminum dichloride and ethyl aluminum dioxide, triethyl aluminum and diethyl aluminum ethoxide and diethyl aluminum chloride. Can be used in combination. The amount of these organometallic compounds used is not particularly limited, but is preferably within a range of 0.5 to 1000 by weight with respect to the solid catalyst component of the present invention.

In order to improve the stereoregularity of an olefin polymer having 3 or more carbon atoms, it is effective to add (externally add) an electron donating compound such as an ether, an ester or an amine during the polymerization. The amount of the electron-donating compound used for such a purpose is 0.00 based on 1 mol of the organoaluminum compound.
It is 1 to 2 mol, preferably 0.01 to 1 mol. Specific examples of the electron-donating compound in this case can be found in those exemplified for the component (A ₂ ).

2) Olefin The olefin polymerized by the catalyst system of the present invention has the general formula R-CH.
CH ₂ (wherein R is a hydrogen atom or a hydrocarbon residue having 1 to 10 carbon atoms and may have a branching group). Specifically, ethylene, propylene,
There are olefins such as butene-1, pentene-1, hexene-1, 4-methylpentene-1. Preferably,
Ethylene and propylene. In the case of these polymerizations, 50% by weight relative to ethylene, preferably 20
Up to 30 weight percent of the olefins can be copolymerized and up to 30 weight percent of the olefins, especially ethylene, can be copolymerized with propylene. Copolymerization with other copolymerizable monomers (for example, vinyl acetate, diolefin) can also be performed.

3) Coupling The catalyst system of the present invention is applicable not only to ordinary slurry polymerization but also to liquid phase solventless polymerization, solution polymerization, or gas phase polymerization method substantially without using a solvent. To be done. Further, it is also applied to a system in which continuous polymerization, batch polymerization or preliminary polymerization is carried out. As a polymerization solvent in the case of slurry polymerization, a saturated aliphatic or aromatic hydrocarbon such as hexane, heptane, pentane, cyclohexane, benzene, or toluene is used alone or as a mixture. The polymerization temperature is from room temperature to about 200 ° C., preferably 50 ° C. to 150 ° C., and hydrogen can be supplementarily used as a molecular weight regulator at that time.

Experimental Example Example-1 1) Synthesis of Component (A ₁ ) n was dehydrated and deoxygenated in a flask that had been sufficiently replaced with nitrogen.
- introducing from heptane 100 ml then MgCl ₂ 0.
2 _{moles, Ti (O-nC 4 H} 9) 4 and then 0.4 mol introduced and reacted for 2 hours at 95 ° C.. After completion of the reaction, the temperature was lowered to 40 ° C., 30 ml of methylhydrogenpolysiloxane was introduced, and the reaction was carried out for 3 hours. After the completion of the reaction, the purified solid component was washed with n-heptane, and a part thereof was taken out and analyzed for composition. Ti = 15.1% by weight, Mg = 4.
It was 2 weight percent.

2) Manufacture of solid component (A) n was dehydrated and deoxygenated in a flask that had been sufficiently replaced with nitrogen.
-Introduced 100 ml of heptane, and introduced 0.09 mol of the component (A ₁ ) synthesized above in terms of Mg atom. SiCl ₄
0.15 mol was introduced at 30 ° C. for 15 minutes and reacted at 70 ° C. for 2 hours. After completion of the reaction, it was washed with purified n-heptane. Then, 25 ml of n-heptane was mixed with 0.009 mol of diheptyl phthalate, introduced at 70 ° C. for 30 minutes, and reacted at 70 ° C. for 1 hour. After completion of the reaction, it was washed with n-heptane. Then 75 ml of TiCl ₄ at 30 ° C
Was introduced and reacted at 100 ° C. for 3 hours. After the reaction,
It was washed with n-heptane to obtain a solid component (A). When a part of the composition was taken out and the composition was analyzed, Ti was 2.45% by weight.

3) Preparation of catalyst component (A) 500 ml of sufficiently dehydrated and deoxidized n-heptane was synthesized in a stainless steel stirring tank having an internal volume of 1 liter, which was fully replaced with nitrogen and equipped with a stirring and temperature control device. 2.5 g of the catalyst component (A) was introduced, and the mixture was prepared at a stirring tank temperature of 25 ° C. and a stirring rotation speed of 400 rpm.

The preparation is continued for 120 hours. A sample was taken on the way and the polymerization was evaluated.

4) Polymerization of propylene In a stainless steel autoclave with an internal volume of 1.5 liter equipped with a stirrer and temperature controller, vacuum-propylene substitution was repeated several times, and then 500 ml of sufficiently dehydrated and deoxidized n-heptane and triethylaluminum were added. 125 mg, diphenyldimethoxysilane 26.8
Then, 15 mg of the catalyst component prepared in the above manner and 0.1 hour after the preparation was introduced. Then H ₂ 60
Introduce milliliter, raise temperature and pressure, polymerization pressure = 5kg / cm
Polymerization was carried out under the conditions of G, polymerization temperature = 75, and polymerization time = 2 hours. After the polymerization was completed, the obtained polymer slurry was separated by filtration and the polymer was dried. 168.6 grams of polymer were obtained. On the other hand, 0.9 g of polymer was obtained from the excess liquid. All products from boiling heptane extraction test
II (hereinafter abbreviated as T-II) was 98.2 weight percent. MFR = 5.7 (g / 10 minutes), polymer bulk specific gravity = 0.435 (g
/ cc).

Hereinafter, the polymerization evaluation results of the samples in the middle are shown in Table-I.

Comparative Example-1 In the preparation of the catalyst component (A) of Example-1, the preparation was performed in exactly the same manner except that the amount of the catalyst component (A) introduced was 1.0 g. Polymerization was performed in exactly the same manner. The results are shown in Table-II.

Example-2 1) Production of solid component (A) n was dewatered and deoxygenated in a flask that had been sufficiently replaced with nitrogen.
— 100 ml of heptane was introduced, and 0.09 mol of the component (A ₁ ) synthesized in the same manner as in Example 1 was introduced in terms of Mg atom. 0.15 mol of SiCl ₄ was introduced at 30 ° C. for 30 minutes and reacted at 70 ° C. for 2 hours. After completion of the reaction, it was washed with purified n-heptane. Next, 0.012 mol of diethyl phthalate was mixed with 15 ml of n-heptane, introduced at 30 ° C. for 30 minutes, and reacted at 70 ° C. for 1 hour. After completion of the reaction, it was washed with n-heptane. Then 75 ml of TiCl ₄ at 30 ° C
The reaction was conducted at 110 ° C. for 3 hours. After the reaction is completed, n
-Washed with heptane to give catalyst component (A). The Ti content was 3.06 weight percent.

2) Preparation of catalyst component (A) The catalyst was prepared and sampled in exactly the same manner as in Example 1 except that 7.5 g of the catalyst component (A) synthesized above was used in the stirring tank used in Example-1. It was

3) Polymerization of propylene The procedure was exactly the same as in Example-1. The results are shown in Table-3.

In preparation of the solid component (A) of Example -3 Example -1, TiCl ₄ 7
Synthesis of component (A ₁ ), production of solid component (A) and preparation of catalyst component (A) were carried out in the same manner as in Example 1 except that 52 ml of SiCl ₄ was used instead of 5 ml. Polymerization of propylene was carried out in the same manner as in Example 1 except that the thus obtained catalyst component was used. As a result, 151.7 g of a polymer was obtained, T-II = 98.5 weight percent, MFR = 6.2 (g / 10 minutes), and polymer bulk specific gravity =
It was 0.45 (g / cc).

In preparation of the solid component (A) of Example -4 Example -1, SiCl ₄
Synthesis of component (A ₁ ), production of solid component (A) and preparation of catalyst component (A) were carried out in the same manner as in Example 1 except that 0.1 mol of TiCl ₄ was used instead of 0.15 mol. Polymerization of propylene was carried out in the same manner as in Example 1 except that the thus obtained catalyst component was used. As a result, 178.3 g of a polymer was obtained, and T-II was 97.9 weight percent, MFR was 3.9 (g / 10 minutes), and the bulk density of the polymer was 0.41 (g / cc).

[Brief description of drawings]

FIG. 1 is intended to help the understanding of the technical content of the present invention regarding the Ziegler catalyst.

Claims (1)

[Claims] 1. The following solid component (A) is obtained as a slurry in an inert solvent, at which time the slurry concentration is adjusted.
5 g catalyst component (A) / liter Inert solvent or more, a method for preparing an olefin polymerization catalyst component comprising a solid component (A), a solid component (A) the following component (A ₁ ), a component (A ₂ ) and a contact product of component (A ₃ ), component (A ₁ ) magnesium dihalide, titanium tetraalkoxide and / or polymer thereof, and general formula (R ¹ is a hydrocarbon residue), a contact product of a polymer silicon compound having a structure represented by the following: component (A ₂ ) aromatic carboxylic acid ester, component (A ₃ ) of the following components (a) and (b) At least one (however, the amount of the component (a) and the component (b) used is within the range of 0.1 to 10 in atomic ratio with respect to the magnesium compound constituting the component (A ₁ )), (a) General A compound represented by the formula TiX ₄ (where X is halogen), and (b) a compound represented by the general formula SiX ₄ (where X is halogen).