JP2607152B2 - Method for producing olefin polymer - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing an olefin polymer. More specifically, by supporting the catalyst component on an inorganic carrier, it is possible to polymerize an olefin with excellent polymerization activity even when the amount of aluminoxane used is reduced, and the bulk specific gravity is large, and the olefin polymer having excellent powder properties is obtained. The present invention relates to a method for producing a coalescence.

[Conventional technology and its problems] As a homogeneous catalyst for olefin polymerization, a so-called Kaminski catalyst is well known. It is known that this catalyst has a very high polymerization activity and, for example, in propylene polymerization, any of atactic polypropylene, isotactic polypropylene and syndiotactic polypropylene can be produced. (Ma
kromol. Chem. Rapid Commum. 4, 417-421 (1983), Angew.
Chem. Int. Ed. Engl. 24, 507-508 (1985), J. Am. Chem. So
c.1987.109,6544-6545, J.Am.Chem.Soc.1988.110,6255
However, the bulk specific gravity of the polymer obtained from these homogeneous catalysts was small, and it was difficult to obtain a polymer having excellent powder properties.

On the other hand, attempts have been made to carry out olefin polymerization using a catalyst in which one or both components of a transition metal compound and an aluminoxane are supported on a particulate carrier. For example, as a method of using a particulate polymer as a carrier, JP-A-63-92621, JP-A-63-260903 and the like can be mentioned.

Further, as a method using an Mg compound as a carrier, Japanese Patent Application Laid-Open
-230802, JP-A-63-168408, JP-A-63-168409, JP-A-63-175004, JP-A-64-6003, JP-A-64-6004, JP-A-64-6005, JP-A-64- JP-A-11104 and JP-A-64-11105 have been proposed. Further, as a method of carrying out polymerization by supporting a catalyst on an inorganic oxide carrier such as silica, silica / alumina and alumina, JP-A-61-108610 and JP-A-
61-276805, JP-A-61-296008, JP-A-63-22804, JP-A-63-280703, JP-A-63-51407, JP-A-63-54403,
JP-A-63-61010, JP-A-63-66206, JP-A-63-89505
No., JP-A-63-152608, JP-A-63-213504, JP-A-63-
Each publication of 248803 has been proposed.

However, even when olefin polymerization is carried out using a solid catalyst component supported on an inorganic carrier in these prior arts, the polymerization activity is low, and the powder properties such as the bulk specific gravity of the produced polymer are also insufficient. There was a problem that only results could be obtained.

The present inventors have conducted studies to solve the above problems, and as a result, by using a transition metal compound [B] described later as a transition metal compound component, the polymerization activity is high, and the bulk specific gravity is large. The inventors have found that a polymer having excellent properties can be obtained, and have arrived at the present invention based on this finding.

[Means for Solving the Problems] That is, the present invention provides (1) [A] an inorganic particulate carrier, and [B] a transition metal compound represented by the general formula [I]. (However, M represents a transition metal of titanium, zirconium or hafnium, and Y represents silicon or germanium.
¹ _n ▼ -C ₅ H _4-n and ▲ R ¹ _q ▼ -C ₅ H _4-q represent an unsubstituted or substituted cyclopentadienyl group, and n and q are integers of 0 to 4, Does not take the value 0. Each R ¹ may be the same or different from each other, and represents hydrogen, a silyl group or a hydrocarbon group, but the position and type of R ¹ on the cyclopentadienyl ring are arranged such that no symmetry plane including M exists. Shall be taken. Each R ² may be the same or different and represents a hydrogen or hydrocarbon group. X may be the same or different and represents a hydrogen, a halogen or a hydrocarbon group. In addition, dimethylsilyl (cyclopentadienyl) (methylcyclopentadienyl) zirconium dichloride is excluded. ), [C] aluminoxane, wherein a solid catalyst component in which either [B] or [C] or both [B] and [C] components are supported on [A] is used. And a method for producing an olefin polymer characterized by polymerizing an olefin.

The solid catalyst component [A] used in the method of the present invention is an organic particulate carrier. Specifically, SiO ₂ ,
Al ₂ O ₃ , MgO, ZrO ₂ , TiO ₂ , B ₂ O ₃ , CaO, ZnO, etc., or a mixture thereof. These inorganic particulate carriers are usually used after firing at 100 to 1,000 ° C, preferably 200 to 900 ° C.

The properties of the carrier vary depending on its type and manufacturing method,
Particles having a particle size in the range of 5 to 200 μm, preferably 10 to 100 μm are used.

Further, these carriers may be preliminarily subjected to a preliminary contact treatment with an organoaluminum compound or a halogen-containing silane compound prior to supporting the transition metal compound or the aluminoxane.

The solid catalyst component [B] used in the method of the present invention is a transition metal compound having a bridged bis-substituted cyclopentadienyl bridge-type bidentate ligand. In the general formula [I], M is a transition metal of titanium, zirconium or hafnium, preferably zirconium. Y is silicon or germanium.
The number of substituents on the two cyclopentadienyl rings may be any from unsubstituted to four-substituted, but at least one of the cyclopentadienyl rings has a substituent.

Each R ¹ may be the same or different from each other, hydrogen, a silyl group or a hydrocarbon group (an alkyl having 1 to 20 carbon atoms, alkenyl, aryl, alkylaryl, arylalkyl, etc.) exhibit, R ¹ And the type on the cyclopentadienyl ring are arranged such that no symmetry plane including M exists.

Examples of the silyl group include a trimethylsilyl group, a triethylsilyl group, and a triphenylsilyl group. Examples of the hydrocarbon group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a phenyl group, a tolyl group, a biphenyl group, and a naphthyl group. . Each R ² may be the same or different and is hydrogen or the above-mentioned hydrocarbon group. X is hydrogen, halogen such as fluorine, chlorine, bromine and iodine, or the above-mentioned hydrocarbon group.

Non-limiting examples of the above transition metal compounds include dimethylsilylbis (methylcyclopentadienyl) zirconium dichloride, dimethylsilylbis (t-butylcyclopentadienyl) zirconium chloride, dimethylsilyl (cyclopentadienyl) (t -Butylcyclopentadienyl) zirconium dichloride, dimethylsilyl (methylcyclopentadienyl) (t-butylcyclopentadienyl) zirconium dichloride, dimethylgermylbis (methylcyclopentadienyl) zirconium dichloride, dimethylsilyl (methylcyclo Pentadienyl) (2,4-dimethylcyclopentadienyl) zirconium dichloride, dimethylsilylbis (2,4-dimethylcyclopentadienyl) zirconium dichloride, dimethylsilylbis (2,3,5- Zirconium compounds such as dimethylcyclopentadienyl) zirconium dichloride and dimethylgermylbis (2,4-dimethylcyclopentadienyl) zirconium dichloride, dimethylsilylbis (methylcyclopentadienyl) titanium dichloride, dimethylsilylbis (2 Titanium compounds such as 1,4-dimethylcyclopentadienyl) titanium dichloride and dimethylsilylbis (2,3,5-trimethylcyclopentadienyl) titanium dichloride, dimethylsilylbis (methylcyclopentadienyl) hafnium dichloride, dimethylsilyl Hafnium compounds such as bis (2,4-dimethylcyclopentadienyl) hafnium dichloride and dimethylsilylbis (2,3,5-trimethylcyclopentadienyl) hafnium dichloride can be given.

The solid catalyst component [C] used in the method of the present invention has the general formula [II] or the general formula [III], Is an organoaluminum compound represented by R ³ is a hydrocarbon group such as a methyl group, an ethyl group, a propyl group, and a butyl group, and is preferably a methyl group or an ethyl group. m is 4 ~
It is an integer of 60, preferably 6 or more. Processes for producing compounds of this type are known. For example, trialkyl is added to a hydrocarbon medium suspension of a compound containing adsorbed water or a salt containing water of crystallization (eg, copper sulfate hydrate, aluminum sulfate hydrate). A method of reacting by adding aluminum can be exemplified.

In the present invention, the following method can be employed as a method for supplying aluminoxane [C] to the polymerization reaction system.

(1) A method in which only a transition metal compound [B] is supported on an inorganic particulate carrier [A] as a solid catalyst component, and the solid catalyst component and aluminoxane [C] are respectively supplied to a polymerization reaction system.

(2) A method in which only an aluminoxane [C] is supported on an inorganic particulate carrier [A] as a solid catalyst component, and the solid catalyst component and the transition metal compound [B] are respectively supplied to a polymerization reaction system.

(3) A method in which both a transition metal compound [B] and an aluminoxane [C] are supported on an inorganic particulate carrier [A] as a solid catalyst component, and the solid catalyst component is supplied to a polymerization reaction system.

(4) A method in which the solid catalyst component of (2) is used as the solid catalyst component and aluminoxane [C] is supplied to the polymerization reaction system together with the solid catalyst component and the transition metal compound [B].

(5) As the solid catalyst component, the solid catalyst component of (3) above is used, and aluminoxane [C] is used together with the solid catalyst component.
Is supplied to the polymerization reaction system.

In the present invention, the method for supporting the transition metal compound [B] on the inorganic particulate carrier [A] includes the following (a) to (a).
The method (c) can be adopted.

(A) A method of forming a solid catalyst component by bringing a solution of a transition metal compound into contact with an inorganic particulate carrier.

(B) A method of forming a solid catalyst component by contacting a suspension of an inorganic particulate carrier dispersed in a solution of a transition metal compound with a solvent insoluble or hardly soluble in the transition metal compound (c) A method of forming a solid catalyst component by distilling off a solvent from a suspension of an inorganic particulate carrier dispersed in a solution of the above.

Further, as a method of supporting the aluminoxane [C] on the inorganic particulate carrier [A], the following methods (d) and (e) can be employed.

(D) A method of forming a solid catalyst component by contacting a suspension of an inorganic particulate carrier dispersed in a solution of aluminoxane with a solvent insoluble or hardly soluble in aluminoxane.

(E) A method of forming a solid catalyst component by distilling off a solvent from a suspension of an inorganic particulate carrier dispersed in a solution of aluminoxane.

As a method for supporting both the transition metal compound [B] and the aluminoxane [C] on the inorganic particulate carrier [A], the following methods (f) to (i) can be employed.

(F) contacting a suspension of the inorganic particulate carrier dispersed in a solution of aluminoxane with an insoluble or sparingly soluble solvent of aluminoxane to form an aluminoxane-supported carrier; A method in which a solid catalyst component is formed by contacting a solution or distilling off a solvent from a suspension of the supported carrier dispersed in a solution of a transition metal compound.

(G) After forming the aluminoxane-supported carrier by distilling the solvent from the suspension of the inorganic particulate carrier dispersed in the aluminoxane solution, the carrier and the transition metal compound solution are contacted. Alternatively, a method of forming a solid catalyst component by distilling off a solvent from a suspension of the supported carrier dispersed in a solution of a transition metal compound.

(H) A transition metal compound-supported carrier is formed by contacting a transition metal compound solution with an inorganic particulate carrier, and then the suspension in which the carrier is dispersed in an aluminoxane solution and the aluminoxane are insoluble or difficult to dissolve. A method of forming a solid catalyst component by contacting with a soluble solvent or distilling off the solvent from a suspension of the supported carrier dispersed in a solution of aluminoxane.

(I) After the transition metal compound-supported carrier is formed by distilling the solvent from the suspension of the inorganic particulate carrier dispersed in the solution of the transition metal compound, the carrier is dispersed in the aluminoxane solution. A method of forming a solid catalyst component by contacting the suspension with an insoluble or sparingly soluble solvent of aluminoxane, or by distilling off the solvent from the suspension of the supported carrier dispersed in a solution of aluminoxane. .

As a soluble solvent for the transition metal compound [B], for example,
Examples thereof include aromatic hydrocarbons such as benzene, toluene, ethylbenzene, and xylene, and halogen-containing hydrocarbons such as chlorobenzene and dichloroethane.

Examples of the insoluble or hardly soluble solvent of the transition metal compound [B] include pentane, hexane, decane, dodecane,
Examples thereof include aliphatic or alicyclic hydrocarbons such as cyclohexane.

As a soluble solvent of aluminoxane [C], for example,
Examples thereof include aromatic hydrocarbons such as benzene, toluene, ethylbenzene, and xylene.

Examples of the insoluble or poorly soluble solvent for aluminoxane [C] include pentane, hexane, decane, dodecane,
Examples thereof include aliphatic or alicyclic hydrocarbons such as cyclohexane.

When the solid catalyst component prepared by the above method contains the transition metal compound [B] per 100 g of the inorganic particulate carrier, the transition metal atom concentration is 0.01 to 500 mmol, preferably 0.05 to 0.05 mmol.
Contains ~ 200 mmol. When the aluminoxane [C] is contained, the aluminum atom concentration is 1 to 1.
It contains 50,000 mmol, preferably 50 to 10,000 mmol.

Furthermore, when both the transition metal compound [B] and the aluminoxane [C] are contained, the content is within the above range, respectively. However, the atomic ratio of aluminum to the transition metal (Al / M) is preferably 1 to 2,000, preferably Ranges from 5 to 1500.

In the method of the present invention, the olefin used in the polymerization reaction is ethylene, propylene, 1-butene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-octene.
Α-olefins such as decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, and 1-eicosene, and a mixture of two or more of these can be used for polymerization. The above α-olefins and conjugated and non-conjugated dienes such as butadiene, 1,4-hexadiene, 1,4-pentadiene, 1,7-octadiene, 1,8-nonadiene, 1,9-decadiene and the like, or It is also effective for copolymerization with styrene or a cyclic olefin such as cyclopropane, cycloten, cyclohexene, norbornene, dicyclopentadiene and the like.

The polymerization method used in the method of the present invention can be either liquid phase polymerization or gas phase polymerization. In the liquid phase polymerization, an inert hydrocarbon may be used as a solvent, or a liquefied olefin itself such as liquefied propylene and liquefied butene-1 may be used as a solvent.

As the polymerization solvent, benzene, toluene, ethylbenzene, aromatic hydrocarbons such as xylene, butane, isobutane, pentane, hexane, octane, decane, dodecane, hexadecane, aliphatic hydrocarbons such as octadecane,
Examples thereof include alicyclic hydrocarbons such as cyclopentane, methylcyclopentane, cyclohexane, and cyclooctane, and petroleum fractions such as gasoline, kerosene, and light oil.

The concentration of transition metal atoms in the polymerization reaction system in the method of the present invention is not particularly limited, but is preferably in the range of 10 ^-2 to 10 ^-10 mol / in terms of transition metal atom concentration. Also,
There is no particular limitation on the amount of aluminoxane used,
The molar ratio of Al / transition metal atom is 10 or more, preferably 20 or more.

There is no particular limitation on the olefin pressure of the polymerization reaction system, preferably in the range of normal pressure to 50 kg / cm ² G, is not particularly limited to the polymerization temperature usually, -50～230 ° C., preferably It is in the range of −30 to 100 ° C. The molecular weight at the time of polymerization can be adjusted by known means, for example, by selecting a temperature or introducing hydrogen.

In the method of the present invention, it is preferable to carry out prepolymerization of the olefin in the presence of a solid catalyst component containing a transition metal compound prior to polymerization of the olefin. The prepolymerization is carried out by polymerizing 0.01 to 100 g, preferably 0.1 to 50 g of olefin per 1 g of the solid catalyst. Examples of the olefin used for the prepolymerization include ethylene, propylene, 1-butene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene,
Tetradecene can be exemplified.

[Effects of the Invention] According to the present invention, even when the amount of aluminoxane used is reduced, the polymerization activity does not decrease, the bulk specific gravity is large, and an olefin polymer excellent in powder properties can be produced.

[Examples] Next, the present invention will be specifically described with reference to Examples.

Example 1 [Preparation of solid catalyst component] In a 300 ml glass reaction vessel, 2 g of silica (# 952, manufactured by Fuji Devison Chemical Co., Ltd.) calcined at 800 ° C for 12 hours and 20 ml of toluene were added to form a suspension. To this, a 10 ml toluene solution containing methylaluminoxane (molecular weight: 990) manufactured by Tosoh Akzo Co., Ltd. corresponding to 5 mmol of Al atoms was added. After stirring at room temperature for 30 minutes, nitrogen was flowed for 1 hour to distill off toluene, and 0.05 mmol of dimethylsilylbis (2,2
50 ml of a toluene solution containing 4-dimethylcyclopentadienyl) zirconium dichloride were added. After stirring at room temperature for 30 minutes, the solid catalyst component was prepared by flowing nitrogen for 2 hours and distilling off toluene.

[Preliminary polymerization] After adding 50 ml of purified toluene and the whole amount of the solid catalyst component under a nitrogen atmosphere to a 300 ml glass reaction vessel, propylene was allowed to flow at room temperature for 3 hours. After flowing propylene, the inside of the system was replaced with nitrogen, and nitrogen was further flown at room temperature for 10 hours to distill off toluene.

Example 2 [Polymerization] In a 1 L SUS gas-phase autoclave sufficiently purged with nitrogen, 50 g of polypropylene powder (manufactured by Chisso Petrochemical Co., Ltd.) and Tosoh Co., Ltd. corresponding to 10 mmol of Al atoms were added.
After adding 20 ml of a toluene solution containing methylaluminoxane (molecular weight: 990) manufactured by Akzo Co., Ltd., nitrogen was flowed for 1 hour to distill off toluene.

Then, the entire amount of the pre-polymerized solid catalyst component prepared in Example 1 was added. Total pressure of 10 kg / cm ^{2 with} propylene
G and polymerization was carried out at 50 ° C. for 2 hours. After completion of the polymerization, the total yield of the obtained polymer was 130 g, the catalytic activity was 8.6 kg / gZr · hr, and the apparent bulk specific gravity was 0.44 g / ml.

Example 3 [Polymerization] In a gas-phase autoclave made of SUS having an inner volume of 1 L and sufficiently purged with nitrogen, 30 g of polypropylene powder (manufactured by Chisso Petrochemical Co., Ltd.) and Tosoh Co., Ltd. equivalent to 10 mmol of Al atoms were added.
After adding 20 ml of a toluene solution containing methylaluminoxane (molecular weight: 990) manufactured by Akzo Co., Ltd., nitrogen was flowed for 1 hour to distill off toluene. Then, the entire amount of the pre-polymerized solid catalyst component prepared in Example 1 was added. The total pressure was adjusted to 10 kg / cm ² G with ethylene, and polymerization was carried out at 50 ° C. for 1.5 hours. After completion of the polymerization, the total yield of the obtained polymer was 118 g, the catalytic activity was 12.2 kg / gZr · hr, and the apparent bulk specific gravity was 0.35 g / ml.

Example 4 [Preparation of solid catalyst component] In a 300 ml glass reaction vessel, 2 g of silica (# 952, manufactured by Fuji Devison Chemical Co., Ltd.) calcined at 800 ° C for 12 hours and 20 ml of toluene were added to form a suspension. To this was added a 50 ml toluene solution containing 0.05 mmol of dimethylsilylbis (2,4-dimethylcyclopentadienyl) zirconium dichloride. After stirring at room temperature for 30 minutes, the solid catalyst component was prepared by flowing nitrogen for 2 hours and distilling off toluene.

Example 5 [Polymerization] In a 1 L SUS gas-phase autoclave sufficiently purged with nitrogen, 50 g of polypropylene powder (manufactured by Chisso Petrochemical Co., Ltd.) and Tosoh Co., Ltd. corresponding to 10 mmol of Al atoms were added.
After adding 20 ml of a toluene solution containing methylaluminoxane (molecular weight: 990) manufactured by Akzo Co., Ltd., nitrogen was flowed for 1 hour to distill off toluene. Then, the entire amount of the solid catalyst component prepared in Example 4 was added. Total pressure of 10 with propylene
The polymerization was carried out at 50 ° C. for 2 hours at a pressure of kg / cm ² G.
After completion of the polymerization, the total yield of the obtained polymer was 120 g, the catalytic activity was 7.4 kg / gZrhr, and the apparent bulk specific gravity was 0.45 g / m.
l.

Comparative Example 1 50 g of polypropylene powder (manufactured by Chisso Petrochemical Co., Ltd.) and 0.05 mmol of dimethylsilylbis (2,4-
Dimethylcyclopentadienyl) 50 ml of a toluene solution containing zirconium dichloride and 20 ml of a toluene solution containing methylaluminoxane (molecular weight 990, manufactured by Tosoh Akzo Co., Ltd.) corresponding to 10 mmol of Al atoms were added successively. After flowing for 3 hours, toluene was distilled off. The total pressure was adjusted to 10 kg / cm ² G with propylene, and polymerization was carried out at 50 ° C. for 2 hours. After the completion of the polymerization, the total yield of the obtained polymer was 70 g, the catalytic activity was 2.2 kg / gZr · hr, and the apparent bulk specific gravity was 0.35 g / ml.

[Brief description of the drawings]

1 to 3 are manufacturing process diagrams (flow sheets) for explaining the method of the present invention.

Claims (1)

(57) [Claims] [1] [A] an inorganic particulate carrier, [B] a transition metal compound represented by the general formula [I] (However, M represents a transition metal of titanium, zirconium or hafnium, and Y represents silicon or germanium.)
R ¹ _n ▼ -C ₅ H _4-n and ▲ R ¹ _q ▼ -C ₅ H _{4-q each} represent an unsubstituted or substituted cyclopentadienyl group, and n and q represent 0 to 4
, But does not take the value of 0 at the same time. Each R ¹ may be the same or different from each other, and represents hydrogen, a silyl group or a hydrocarbon group, but the position and type of R ¹ on the cyclopentadienyl ring are arranged such that no symmetry plane including M exists. Shall be taken. Each R ² may be the same or different and represents a hydrogen or hydrocarbon group. X may be the same or different and represents a hydrogen, a halogen or a hydrocarbon group. In addition, dimethylsilyl (cyclopentadienyl) (methylcyclopentadienyl) zirconium dichloride is excluded. ), [C] aluminoxane, wherein a solid catalyst component in which either [B] or [C] or both [B] and [C] components are supported on [A] is used. And polymerizing the olefin.