JPH0826097B2 - Ultra high molecular weight polyethylene manufacturing method - Google Patents

Description

Description: BACKGROUND OF THE INVENTION Technical Field The present invention relates to an ultra high molecular weight polyethylene having a weight average molecular weight of 500,000 to 3,000,000. More specifically, the present invention relates to an ethylene polymerization method characterized by the Ziegler type catalyst used, especially its titanium compound component, and the third component added during polymerization.

Conventionally, as a method of improving the performance of polyethylene, a method of increasing the degree of polymerization to increase the molecular weight has been known. Polyethylene is known to have improved impact resistance, abrasion resistance, stress / crack resistance, chemical resistance, etc. as the molecular weight increases.
Ultra high molecular weight polyethylene is used in industrial materials such as gears and packings. Recently, such ultra-high molecular weight polymers have been attracting attention as raw polymer for ultra-high strength polyethylene fibers.

Prior Art In order to produce ultra high molecular weight polyethylene, that is, in order to increase the degree of polymerization of the polymer, it is important to select the type of solid catalyst component, the type of organoaluminum component, and the polymerization conditions.

However, it is desirable that the solid catalyst component be highly active and give a high molecular weight polymer, but no solid catalyst component satisfying these two conditions has been known so far.

As the organoaluminum component, many of those which give high-molecular weight polyethylene conventionally lack polymerization stability,
Problems such as polymer adhesion and coarse polymer are likely to occur.

Regarding the polymerization conditions, in order to obtain high-molecular-weight polyethylene, the polymerization temperature is often lowered, and the catalytic activity is lowered.
Various problems such as reduced productivity are likely to occur.

From such a point, in order to produce ultra-high molecular weight polyethylene with good productivity and stable polymerization conditions,
It is understood that there are still points to be improved.

The present inventors have already proposed a method for producing an ultrahigh molecular weight polyethylene having a molecular weight of 500,000 to 3,000,000 by combining a so-called highly active catalyst component containing titanium, magnesium and halogen as described above and a specific organoaluminum component. It has been proposed (see JP-A-59-68311).

This method can produce ultra-high molecular weight polyethylene to some extent, but there is a point that it is necessary to improve the molecular weight and polymer properties of the resulting polymer, and the polymerization temperature cannot be increased even under the polymerization conditions. Etc. were still insufficient.

SUMMARY OF THE INVENTION The present invention provides a solution to the above-mentioned problems and aims to obtain an ultra high molecular weight polyethylene having a weight average molecular weight of 500,000 to 3,000,000, and contains Ti, Mg and Cl as essential components. It is an object of the present invention to achieve the above object by a catalyst system comprising a solid catalyst component, a specific concentration of organoaluminum component, and a specific electron donor compound.

Therefore, the method for producing ultra-high molecular weight polyethylene according to the present invention comprises the following components (A), (B) and (C):
A catalyst system composed of ethylene or ethylene and α-
Weight average molecular weight of 50
It is characterized by producing 1 to 3 million polyethylene.

Component (A) Ziegler type catalyst comprising a solid composition containing tetravalent titanium, magnesium and halogen as essential components (hereinafter referred to as component (a)) and an organoaluminum component having 3 or more carbon atoms. A composition obtained by prepolymerizing 5 g or more per 1 g of the component (a).

Component (B) Organoaluminum compound Component (C) Silicon compound represented by the general formula R ⁶ _b Si (OR ⁷ ) _4-b (wherein R ⁶ is a hydrocarbon residue having 1 to 20 carbon atoms or halogen) , R ⁷ is a hydrocarbon residue having 1 to 20 carbon atoms, and b is a number of 0 ≦ b <4), a boron compound represented by the general formula R ⁸ _c B (OR ⁹ ) _3-c (here Wherein R ⁸ is a hydrocarbon residue having 1 to 20 carbon atoms or halogen, R ⁹ is a hydrocarbon residue having 1 to 20 carbon atoms, and c is 0.
≦ c <3), or a phosphorus compound represented by the general formula PR ¹⁰ _d (OR ¹¹ ) _3-d (wherein R ¹⁰ is a hydrocarbon residue having 1 to 20 carbon atoms or halogen, R ¹¹ is a hydrocarbon residue having 1 to 20 carbon atoms, d
Is a number 0 ≦ d <3).

Effects The present invention is superior to the above-mentioned conventional technique in producing ultrahigh molecular weight polyethylene in the following points.

I. Since it has high activity, the so-called decatalysis step can be omitted.

B. Since it is not necessary to lower the polymerization temperature in order to increase the molecular weight, the productivity is good.

The above effects (1) and (2) can be achieved only by using the catalyst system comprising the component (A), the component (B) and the component (C) according to the present invention. That is, the component (A) is necessary for omitting the decatalysis step, and the components (B) and (C) are necessary for improving the productivity.

Conventionally, the Mg-containing solid catalyst of component (A) (generally a Mg-supported transition metal catalyst component) has been used as an α, such as ethylene, propylene, etc.
It is known that polymerizing olefins gives polymers with high activity. However, in order to produce ultra-high molecular weight polyethylene with these catalysts, it is necessary to lower the polymerization temperature, which results in poor productivity, so this catalyst is usually not used. The present invention
The use of a specific amount of organoaluminum component (component B) and a specific electron donor (component C) allowed the use of a Mg-supported transition metal catalyst component (component A) in the production of ultra high molecular weight polyethylene. It is a thing.

In addition, so-called “granulation” is often difficult for ultra-high molecular weight polyethylene, and polyethylene powder is often directly used as a product. In that case, the powder form is extremely important. In the present invention, the component (A)
It is also possible to produce ultra-high molecular weight polyethylene in good powder form by producing.

Detailed Description of the Invention Catalyst and Production Thereof The catalyst of the present invention is composed of component (A), component (B) and component (C).

Component (A) Component (A) is a solid catalyst component (hereinafter referred to as component (a)) of a Ziegler type catalyst comprising a solid composition containing tetravalent titanium, magnesium and halogen as essential components and an organoaluminum component. An olefin having 3 or more carbon atoms is preliminarily polymerized in the presence of 5 g or more per 1 g of the component (a).

The component (a), that is, the solid catalyst component of the Ziegler type catalyst having these three components as essential components, is well known including the production method thereof, and various purposeful ones including modified products thereof. Can be used. Here, "containing as an essential component" means that, if Ti, Mg and halogen are contained, a purposeful additional component may coexist. Specifically, for example, an element such as silicon, aluminum, or boron can be included.

Specific examples of the component (a) are described in, for example, JP-A-53-45688.
No. 54-3894, No. 54-31092, No. 54-39483, No. 54-39483
54-94591, 54-118484, 54-131589, 55
-75411, 55-90510, 55-90511, 55-127
No. 405, No. 55-147507, No. 55-155003, No. 56-18609
No. 56-70005, No. 56-72001, No. 56-86905,
56-90807, 56-155206, 57-3803, 57
-34103, 57-92007, 57-121003, 58-53
No. 09, No. 58-5310, No. 58-5311, No. 58-8706, No.
58-27732, 58-32604, 58-32605, 58-6
7703, 58-117206, 58-127708, 58-1837
08, 58-183709, 59-149905, 59-149906
No., each publication, etc. can be found.

The component (a) can be prepared by any purposeful method, and some of such methods are described in the above-mentioned publications. Is.

(A) A method in which a magnesium halide, an electron donor compound, and a titanium-containing compound are contacted with each other and, if necessary, treated with a specific solvent.

(B) A method of treating alumina or magnesia with a phosphorus halide compound, and contacting it with a magnesium halide, an electron donor compound and a titanium halogen-containing compound.

(C) A method of bringing an electron donor compound, a titanium halogen compound and / or a halogen compound of silicon into contact with a solid component obtained by bringing magnesium halide, titanium tetraalkoxide and a specific polymer silicon compound into contact with each other, if necessary. .

(D) A method in which a magnesium compound is dissolved with titanium tetraalkoxide and an electron donor compound, and a halogenating agent or a titanium halogen compound is added to the resulting liquid material to bring the titanium compound into contact with the precipitated solid component.

(E) A method in which an organomagnesium compound such as a Grignard reagent is allowed to act with a halogenating agent, a reducing agent, etc., and then an electron donor compound and a titanium compound are brought into contact with it.

(F) A method of bringing a halogenating agent and / or a titanium compound into contact with an alkoxymagnesium compound in the presence or absence of an electron donor compound.

In these methods, the magnesium compound used is magnesium halide (halogen is chlorine, bromine, or the like, but chlorine is particularly preferable), dialkoxymagnesium (as the alkyl of the alkoxy group, C _1- ). C ₁₀ is preferred), alkoxy magnesium halides (see above for alkoxy groups and halogens), magnesium oxyhalides (see above for halogens), dialkyl magnesium (see alkyl groups above for alkoxy groups), magnesium oxide, Magnesium hydroxide, magnesium carboxylate (preferably a salt of a monocarboxylic acid having about 1 to 20 carbon atoms) and the like can be mentioned.

The tetravalent titanium compound used for producing the component (a) is represented by the general formula Ti (OR ¹ ) _4-n X _n (wherein R ¹ is a hydrocarbon residue, preferably 1 carbon atom). To about 10, X represents halogen, and n represents a number of 0n4). Specific examples include TiCl ₄ , TiBr ₄ , Ti (OC ₂
H ₅ ) Cl ₃ , Ti (OC ₂ H ₅ ) ₂ Cl ₂ , Ti (OC ₂ H ₅ ) ₃ Cl, Ti (OiC ₃ H ₇ ) C
l ₃ , Ti (OnC ₄ H ₉ ) Cl ₃ , Ti (OnC ₄ H ₉ ) ₂ Cl ₂ , Ti (OC ₂ H ₅ ) Br ₃ , T
i (OC ₂ H ₅ ) (OC ₄ H ₉ ) ₂ Cl, Ti (OnC ₄ H ₉ ) ₃ Cl, Ti (OC ₆ H ₅ ) Cl ₃ , T
i (OiC ₄ H ₉ ) ₂ Cl ₂ , Ti (OC ₅ H ₁₁ ) Cl ₃ , Ti (OC ₆ H ₁₃ ) Cl ₃ , Ti (OC
₂ H ₅ ) ₄ , Ti (OnC ₃ H ₇ ) ₄ , Ti (OnC ₄ H ₉ ) ₄ , Ti (OiC ₄ H ₉ ) ₄ , Ti (O
_{nC 6 H 13) 4, Ti} (OnC 8 H 17) 4, Ti _{[OCH 2 CH (C 2 H 5} ) C 4 H 9 ] is _4, and the like.

The titanium compound may be a molecular compound obtained by reacting TiX ' ₄ (where X'represents halogen) with an electron donor. Specific examples include TiCl ₄ CH ₃ COC ₂ H ₅ , TiCl ₄
・ CH ₃ CO ₂ C ₂ H ₅ , TiCl ₄・ C ₆ H ₅ NO ₂ , TiCl ₄・ CH ₃ COCl, TiCl
₄・ C ₆ H ₅ COCl, TiCl ₄・ C ₆ H ₅ CO ₂ C ₂ H ₅ , TiCl ₄・ ClCOC ₂ H ₅ ,
TiCl ₄ , C ₄ H ₄ O, etc.

It has been mentioned above that an electron donor compound can be used when producing the component (a).

Examples of electron donors that can be used for producing the solid component (a) include alcohols, phenols, ketones, aldehydes, carboxylic acids, esters of organic acids or inorganic acids, ethers, acid amides, acid anhydrides. Examples thereof include oxygen-containing electron donors such as the class, nitrogen-containing electron donors such as ammonia, amine, nitrile, and isocyanate.

More specifically, (i) methanol, ethanol, propanol, pentanol, hexanol, octanol, dodecanol, octadecyl alcohol, benzyl alcohol, phenylethyl alcohol, cumyl alcohol, isopropylbenzyl alcohol, etc.
To 18 alcohols, (b) phenol, cresol, xylenol, ethylphenol, propylphenol, cumylphenol, nonylphenol, naphthol and the like which may have an alkyl group having 6 to 6 carbon atoms
25 phenols, (c) Acetone, methyl ethyl ketone, methyl isobutyl ketone, acetophenone, benzophenone and other C 3 -C 15 ketones, (d) acetaldehyde, propionaldehyde, octyl aldehyde, benzaldehyde, tolualdehyde, naphthaldehyde, etc. Aldehydes having 2 to 15 carbon atoms,
(D) Methyl formate, methyl acetate, ethyl acetate, vinyl acetate, propyl acetate, octyl acetate, cyclohexyl acetate, ethyl propionate, methyl butyrate, ethyl valerate,
Ethyl stearate, ethyl chloroacetate, ethyl dichloroacetate, methyl methacrylate, ethyl crotone, ethyl cyclohexanecarboxylate, methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, octyl benzoate, cyclohexyl benzoate, benzoate Phenyl acid, benzyl benzoate, methyl toluate, ethyl toluate, amyl toluate, ethyl ethyl benzoate, methyl anisate, ethyl anisate, ethyl ethoxybenzoate, diethyl phthalate, dibutyl phthalate, diheptyl phthalate, γ -Butyrolactone, α-valerolactone,
Organic acid esters having 2 to 20 carbon atoms such as coumarin, phthalide, ethylene carbonate, etc., (f) inorganic acid esters such as ethyl silicate, butyl silicate, phenyl triethoxysilane and the like, (g) Acid halides having 2 to 15 carbon atoms such as acetyl chloride, benzoyl chloride, toluic acid chloride, anisic acid chloride, phthaloyl chloride and isophthaloyl chloride, (thi) methyl ether, ethyl ether, isopropyl ether, butyl ether, amyl ether, tetrahydrofuran, C2-C20 ethers such as anisole and diphenyl ether, acetic amides such as (li) acetic acid amide, benzoic acid amide and toluic acid amide, (nu) methylamine,
Ethylamine, diethylamine, tributylamine, piperidine, tribenzylamine, aniline, pyridine,
Examples thereof include amines such as picoline and tetramethylethylenediamine, and nitriles such as (l) acetonitrile, benzonitrile and tolunitrile. It is also possible to use two or more of these.

The amount of each component constituting the component (a) may be any amount as long as the effects of the present invention are recognized, but generally, the following range is preferable. The titanium compound is used in a molar ratio of 1 × 10 ^{−3 to} 1000, preferably 0.01 to 10, with respect to the magnesium compound, and the halogen is also used in a molar ratio with respect to the magnesium compound. In the range of 0.1 to 100, preferably in the range of 1 to 50.

When an electron-donating compound is used as an optional component, the amount used is 1 × with respect to the magnesium compound.
Within a range of 10 ^{−3 to} 100, preferably within a range of 0.01 to 10,
Is.

The component (A) of the present invention is obtained by preliminarily polymerizing the solid composition, that is, the component (a), with an olefin having 3 or more carbon atoms in an amount of 5 g or more per 1 g of the component (a). Here, "preliminarily polymerizing the component (a)" means
It means that the component (a) is used as a solid catalyst component of the Ziegler type catalyst to polymerize an olefin to form a small amount of polyolefin on the component (a). The prepolymerization conditions are not particularly limited, but the following conditions are generally preferred. The polymerization temperature is 0 to 80 ° C, preferably 10 to 60 ° C. The amount of polymerization is 5 g or more per 1 g of the solid composition, but it is usually up to 50 g due to the nature of prepolymerization. The preferred amount of prepolymerization is 10 to 20 grams.

As the organoaluminum component in the prepolymerization, those generally known as cocatalysts for Ziegler type catalysts can be used.

As a specific example, Al (C ₂ H ₅ ) ₃ , Al (iC ₄ H ₉ ) ₃ , Al (nC ₄ H ₉ )
_{3, Al (C 5 H 11} ) 3, Al (C 8 H 17) 3, Al (C 10 H 21) 3, Al (C 2 H 5) 2 C
_{l, Al (iC 4 H 9} ) 2 Cl, Al (C 2 H 5) 2 H, Al (iC 4 H 9) 2 H, Al (C 2 H 5)
₂ (OC ₂ H ₅ ), etc. Of these, Al (C ₂ H ₅ ) ₃ and Al (iC ₄ H ₉ ) ₃ are preferable.

The amount of the organoaluminum component used during the prepolymerization is 1 to 20, preferably 2 to 10, in terms of Al / Ti (molar ratio) with respect to the titanium component in the solid composition. Further, at the time of prepolymerization, the electron donor compound as described above, such as alcohol, ester or ketone, can be added.

Examples of olefins having 3 or more carbon atoms used in the prepolymerization include propylene, 1-butene, 1-hexene, 4-methyl-pentene-1 and the like. Propylene is particularly preferable.

Thus, the component (A) of the present invention is obtained by prepolymerizing 5 g or more of an olefin having 3 or more carbon atoms in a solid composition containing titanium, magnesium and halogen as essential components.

Component (B) Component (B) is an organoaluminum compound. As a specific example, Or (Here, R ² and R ³ may be the same or different and are a hydrocarbon residue or hydrogen having about 1 to 20 carbon atoms, and R ⁴ is 1 to 1 carbon atoms.
Hydrocarbon residues of about 20, X is halogen, n and m are numbers 0n <3 and 0 <m <3, respectively. ). Specifically, (a) trialkylaluminum such as trimethylaluminum, triethylaluminum, triisobutylaluminum, trihexylaluminum, trioctylaluminum, tridecylaluminum, (b) diethylaluminummonochloride, diisobutylaluminummonochloride,
Examples thereof include alkylaluminum halides such as ethylaluminum sesquichloride and ethylaluminum dichloride, (c) diethylaluminum hydride, diisobutylaluminum hydride, (d) aluminum alkoxides such as diethylaluminum ethoxide and diethylaluminum phenoxide.

In addition to these organoaluminum compounds (a) to (c), other organometallic compounds such as (1a3, R ⁴ and R ⁵ are hydrocarbon residue of about the same or different carbon atoms which may be 1-20.) The alkyl aluminum alkoxide may be used in combination represented by. 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 diethoxide, triethyl aluminum and diethyl aluminum ethoxide and diethyl aluminum chloride Can be used in combination.

Component (C) Component (C) is a silicon compound, a boron compound or a phosphorus compound each represented by a specific general formula.

Each of these is specifically represented by the following general formula.

That is, the silicon compound has the general formula R ⁶ _b Si (OR ⁷ ).
_4-b (wherein R ⁶ is a hydrocarbon residue having 1 to 20 carbon atoms or halogen, R ⁷ is a hydrocarbon residue having 1 to 20 carbon atoms, and b is a number of 0 ≦ b <4 It is represented by). As a specific example, Si (OCH ₃ ) ₄ , Si (OC ₂ H ₅ ) ₄ , Si (OiC ₃ H ₇ ) ₄ , Si (OnC ₄ H ₉ ) ₄ , Si (OC ₆ H ₅ ) ₄ , (CH _{3) Si (OCH 3) 3} , (CH 3) 2 Si (OCH 3) 2, (CH 3) Si (OC 2 H 5) 3, (C 2 H 5) 2 Si (OC 2 H 5) 2, _{(nC 6 H 11) Si (} OCH 3) 3, (nC 10 H 21) Si (OCH 3) 3, (CH 2 = CH) Si (OCH 3) 3, Cl (CH 2) 3 Si (OCH 3) _{3, (C 6 H 5)} Si (OCH 3) 3, (C 6 H 5) Si (OC 2 H 5) 3, (C 6 H 5) 2 Si (OC 2 H 5) 2, (C 6 H ₅ ) ₂ Si (OCH ₃ ) ₂ , (C ₆ H ₅ ) (CH ₃ ) Si (OCH ₃ ) ₂ , NC (CH ₂ ) ₂ Si (OC ₂ H ₅ ) ₃ , (C ₆ H ₅ ) (CH ₃ ) Si (OC ₂ H ₅ ) ₂ , (nC ₃ H ₇ ) Si (OC ₂ H ₅ ) ₃ , (CH ₃ ) Si (OC ₃ H ₇ ) ₃ , (C ₆ H ₅ -CH ₂ ) Si ( OC ₂ H ₅ ) ₃ , _{Si (OCH 3) 2 Cl 2} , Si (OC 2 H 5) 3 Cl, Si (OC 2 H 5) 2 Cl 2, Si (OiC 3 H 7) Cl 3, Si (OnC 4 H 9) 2 Cl 2 , Si (OCH ₃ ) ₂ Br ₂ , Si (OC ₆ H ₅ ) ₃ Cl, and the like. Of these, preferred are Si (OCH ₃ ) ₄ , Si (OC ₂ H ₅ ) ₄ , Si (OnC ₄ H ₉ ) ₄ , (C ₆ H ₅ ) Si (OC ₂ H ₅ ) ₃ , and (C ₆ H ₅ ) Si (OCH ₃ ) ₃ , etc.

The boron compound has the general formula R ⁸ _c B (OR ⁹ ) _3-c (wherein R ⁸ is a hydrocarbon residue having 1 to 20 carbon atoms or halogen, and R ⁹ is a hydrocarbon residue having 1 to 20 carbon atoms. A group, and c is a number 0 ≦ c <3).

As a specific example, B (OCH ₃ ) ₃ , B (OC ₂ H ₅ ) ₃ , B (OnC ₃ H ₇ ) ₃ , B (OiC ₃ H ₇ ) ₃ , B (OnC ₄ H ₉ ) ₃ , B ( OnC ₆ H ₁₃ ) ₃ , B (OC ₆ H ₅ ) ₃ , B (OC ₆ H ₄ CH ₃ ) ₃ , B (OCH ₃ ) ₂ Cl ₂ , B (OCH ₃ ) Cl ₂ , B (OC ₂ H ₅ ) ₂ Cl, B (OC ₄ H ₉ ) Cl ₂ , (CH ₃ ) B (OC ₂ H ₅ ) ₂ , (C ₂ H ₅ ) B (OC ₂ H ₅ ) ₂ , (C ₆ H ₅ ) B ( OCH ₃ ) ₂ and the like.

The phosphorus compound has the general formula PR ¹⁰ _d (OR ¹¹ ) _3-d (wherein R ¹⁰
Is a hydrocarbon residue having 1 to 20 carbon atoms or halogen,
R ¹¹ is a hydrocarbon residue having 1 to 20 carbon atoms, and d is 0 ≦ d
<Is a number of 3). As a specific example, P (OC
_{H 3) 3, P (OC} 2 H 5) 3, P (OiC 3 H 7) 3, P (OnC 3 H 7) 3, P (OnC 4 H 9) 3, P (OiC 4 H 9) 3, P (OnC ₈ H ₁₅ ) ₃ , P (OnC ₁₀ H ₂₁ ) ₃ , P (OnC ₁₇ H ₃₅ ) ₃ , P (OCH ₃ ) ₂ Cl, P (OC ₂ H ₅ ) ₂ Cl, P (OC ₂ H _{5) Cl 2, P (OnC} 4 H 9) Cl 2, P (CH 3) (OC 2 H 5) 2, P (C 2 H 5) (OCH 3) 2, and the like.

In the above definitions of the Si, B and P compounds, a hydrocarbon residue having about 1 to 20 carbon atoms is preferably a lower alkyl group or a phenyl group, and a halogen is preferably chlorine.

Preparation of Catalyst The catalyst system of the present invention is formed by contacting component (A), component (B) and component (C) at one time or stepwise.

The amount of the organoaluminum compound used as the component (B) is not particularly limited, but is 1 by weight with respect to the component (A) of the present invention.
It is preferably within the range of up to 1000, especially 10 to 300.

The component (C) may be used in a molar ratio of 1 × 10 ⁻³ to 10 with respect to the component (B) of the present invention, and preferably 0.1 to 10.
It is within the range of 1.0.

Polymerization The ultra high molecular weight polyethylene of the present invention is produced by slurry polymerization or gas phase polymerization.

Also, this catalyst system can be used for both continuous polymerization and batch polymerization.
Alternatively, it is also effective as a method of performing prepolymerization. As the polymerization solvent in the case of slurry polymerization, saturated aliphatic or aromatic hydrocarbons such as hexane, heptane, pentane, cyclohexane, benzene, and toluene may be used alone or as a mixture. The polymerization temperature is from room temperature to about 100 ° C,
It is preferably 50 ° C to 85 ° C. Further, about 1 to 20 weight% of propylene and butene-based on ethylene.
Copolymerization with other α-olefins such as 1, hexene-1, etc. is also possible. The ultrahigh molecular weight polyethylene produced according to the present invention has a weight average molecular weight of 500,000 to 3,000,000, especially 6
It ranges from 0 to 2 million. The definition and measurement of weight average molecular weight is well known [eg "polyethylene resin" 46
~ P. 49 (Plastic material course 4) (Nikkan Kogyo Shimbun,
(Showa 44), etc.)].

Experimental Example Example-1 1) Preparation of component (A) 150 ml of sufficiently deaerated and purified n-heptane was placed in a 1 liter flask purged with nitrogen, and then MgCl _{2 was} added.
0.1 mol of (crushed by a ball mill for 24 hours) and 0.03 mol of Ti (OnC ₄ H ₉ ) ₄ were introduced, the temperature was raised to 70 ° C., and the mixture was stirred for 1 hour. Then, n-butanol
0.07 mol was introduced and the reaction was carried out at 70 ° C. for 1 hour. Further, 0.1 mol of SiCl ₄ was introduced at 30 ° C. and reacted at 90 ° C. for 4 hours. After the completion of the reaction, the resultant was washed with n-heptane. Then
Introduce 0.02 mol of dibutyl phthalate at 30 ℃ and
Allowed to react for hours. After the completion of the reaction, the resultant was washed with n-heptane. In addition, 25 ml of TiCl ₄ was introduced at 30 ° C.
The reaction was carried out at 10 ° C for 4 hours. After the completion of the reaction, the resultant was washed with n-heptane. It was used as the component (a) for producing the component (A). Incidentally, when a part of the component (a) was taken out and the composition was analyzed, the Ti content was 3.36% by weight.

Prepolymerization Treatment of Component (a) In a stainless steel stirring tank having an internal volume of 1.5 liter equipped with a stirring and temperature control device, 750 ml of sufficiently dehydrated and deoxidized n-heptane, 3.2 g of triethylaluminum, and component (a) ) Was introduced for 15 grams each. The temperature in the stirring tank was adjusted to 20 ° C., propylene was introduced at a constant rate, and propylene was polymerized for 2 hours. After the completion of the polymerization, it was thoroughly washed with n-heptane. When a part of the product was taken out and the polymerization amount of propylene was examined, it was 9.8 g of propylene per 1 g of the component (a).

2) Polymerization of ethylene Into a stainless steel autoclave having an internal volume of 1.5 liter equipped with a stirring and temperature control device, vacuum-ethylene substitution was repeated several times, and then 800 ml of sufficiently dehydrated and deoxidized n-heptane was introduced, then triethyl aluminum (B) 100 mg was introduced 10 mg as _{(C 6 H 5) Si (} OC 2 H 5) 3 (C) 20.8 milligrams and above synthesized catalyst component (a) component (a). Further, ethylene was introduced to make the total pressure 6 kg / cm ² . The temperature was raised to 75 ° C. and polymerization was carried out for 2 hours. These reaction conditions were kept the same during the polymerization. However, the pressure that decreased as the polymerization proceeded was maintained at a constant pressure by introducing only ethylene. After the completion of the polymerization, ethylene was purged, the contents were taken out from the autoclave, and the polymer slurry was filtered and dried overnight in a vacuum dryer.

 174 grams of polymer (PE) was obtained.

When the molecular weight of the polymerized polymer was measured, the weight average molecular weight (hereinafter abbreviated as Mw) was 1.5330,000. The polymer bulk specific gravity was 0.36 (g / cc).

Example-2 1) Preparation of catalyst component (component (A)) 50 ml of dehydrated and deoxygenated n-heptane was introduced into a flask thoroughly replaced with nitrogen, and then MgCl _{2 was} added.
0.1 mol and 0.2 mol of Ti (O-nBu) ₄ were introduced and reacted at 90 ° C. for 2 hours. After the reaction is completed, lower the temperature to 40 ℃,
12 ml of methylhydrogenpolysiloxane (20 centistoke) was introduced and reacted for 2 hours. The resulting solid component was washed with n-heptane. Next, 0.2 mol of SiCl ₄ and 50 ml of n-heptane were introduced, and the reaction was carried out at 50 ° C. for 2 hours. After completion of the reaction, n-
It was washed with heptane to obtain the component (a). Compositional analysis revealed that Ti = 4.8 weight percent.

Prepolymerization Treatment of Component (a) Under the prepolymerization conditions of Example-1, the amount of triethylaluminum used was 2.4 grams, and the prepolymerization amount was 15.
Preliminary polymerization was carried out in the same manner except that the amount was changed to 2 g to obtain the component (A).

2) Polymerization of ethylene Polymerization of ethylene was carried out under the same conditions as in Example-1. 133 grams of polymer were obtained. The Mw was 1.24 million and the bulk density of the polymer was 0.45 (g / cc).

Comparative Example-1 In the production of the component (A) of Example-2, the component (A) was prepared in the same manner except that propylene was not prepolymerized.
Was produced and ethylene was polymerized in exactly the same manner. 116 grams of polymer was obtained, Mw = 1.22 million and polymer bulk specific gravity = 0.38 (g / cc).

Example-3 1) Production of catalyst component (component (A)) 100 ml of dehydrated and deoxygenated n-heptane was introduced into a flask which had been sufficiently replaced with nitrogen, and then MgCl ₂ was added.
0.1 mol, Ti (OnC ₄ H ₉ ) ₄ 0.195 mol and n-butanol
0.007 mol of each was introduced and reacted at 90 ° C. for 1 hour. After the reaction was completed, the temperature was lowered to 35 ° C., 0.25 mol of 1,3,5,7-tetramethylcyclotetrasiloxane was introduced, and 4
Allowed to react for hours. After completion of the reaction, the produced solid component is n-
Wash with heptane. Then, 0.2 mol of SiCl ₄ was introduced at 30 ° C. for 1 hour and reacted at 90 ° C. for 4 hours. Furthermore, 0.01 mol of phthalic acid chloride was introduced at 90 ° C. for 0.5 hour, and the reaction was carried out at 95 ° C. for 1 hour. After the completion of the reaction, the resultant was washed with n-heptane. Then, 0.1 mol of SiCl ₄ was introduced at 30 ° C. and reacted at 90 ° C. for 6 hours. After completion of the reaction, it was washed with n-heptane to obtain a solid component (a).

Preliminary Polymerization Treatment of Solid Component (a) The prepolymerization conditions of Example-1 were repeated except that a mixture of 2.8 g of triethylaluminum and 0.4 g of diethylaluminum was used instead of triethylaluminum. The component (A) was obtained.

2) In the polymerization conditions of ethylene polymerization in Example 1, triethylaluminum 75 mg, except that the _{(C 6 H 5) Si (} OC 2 H 5) 3 15.6 milligrams, polymerization was carried out in exactly the same conditions. 213 grams of polymer were obtained. The Mw was 1.89 million and the bulk density of the polymer was 0.45 (g / cc).

In the polymerization condition of Comparative Example -2 Example -3, (C ₆ H ₅₎ without using _{Si (OC 2 H 5) 3} , Al (C 2 H 5) 2 (OC 2 H 5) 22
Polymerization was performed under exactly the same polymerization conditions except that 5 mg was used. 184 grams of polymer were obtained, Mw = 1
The polymer bulk specific gravity was 130,000 = 0.40 (g / cc).

Comparative Example-3 In the production of the component (A) of Example-3, the component (A) was produced in exactly the same manner except that the preliminary polymerization amount was changed to 2 g per 1 g of the component (a) to polymerize ethylene. Was done in exactly the same way. 157 grams of polymer are obtained, M
w = 1.37 million and polymer bulk specific gravity = 0.39 (g / cc).

Examples-4 to 8 In the polymerization of Example-3, as a component (C), Table-1
Polymerization of ethylene was performed in exactly the same manner except that the compound shown in 1 was used. The results are shown in Table-1.

Examples-9 to 10 Ethylene was polymerized exactly in the same manner as in Example-1, except that the compounds shown in Table 2 were used as the component (B). The results are shown in Table-2.

Examples-11 to 12 Ethylene was polymerized exactly in the same manner as in Example-2 except that the amount of the component (C) used and the polymerization temperature were changed. The results are shown in Table-3.

[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. A catalyst system composed of the following components (A), (B) and (C) is brought into contact with ethylene or a mixed gas of ethylene and α-olefin to give a weight average molecular weight of 500,000 to A method for producing ultra-high molecular weight polyethylene, which is characterized by producing 3 million polyethylene. Component (A) Ziegler type catalyst comprising a solid composition containing tetravalent titanium, magnesium and halogen as essential components (hereinafter referred to as component (a)) and an organoaluminum component having 3 or more carbon atoms. A composition obtained by preliminarily polymerizing 5 g or more per 1 gram of the component (a), component (B) an organoaluminum compound, component (C) a silicon represented by the general formula R ⁶ _b Si (OR ⁷ ) _4-b Compound (wherein R ⁶ is a hydrocarbon residue having 1 to 20 carbon atoms or halogen, R ⁷ is a hydrocarbon residue having 1 to 20 carbon atoms, and b is a number of 0 ≦ b <4 ), A boron compound represented by the general formula R ⁸ _c B (OR ⁹ ) _3-c (wherein R ⁸ is a hydrocarbon residue having 1 to 20 carbon atoms or halogen, and R ⁹ is 1 to 20 carbon atoms). Is a hydrocarbon residue of, and c is 0
≦ c <3) or a phosphorus compound represented by the general formula PR ¹⁰ _d (OR ¹¹ ) _3-d (wherein R ¹⁰ is a hydrocarbon residue having 1 to 20 carbon atoms or halogen, R ¹¹ is a hydrocarbon residue having 1 to 20 carbon atoms, d
Is a number 0 ≦ d <3).