JPS623163B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing highly stereoregular poly-α-olefins using highly active catalysts. Conventionally, when industrially polymerizing α-olefins such as propylene, a method was developed to increase the activity of the catalyst by supporting the titanium component of the Ziegler-Natsuta catalyst on a carrier, and this method is becoming common for ethylene polymerization catalysts. . However, in the case of α-olefins such as propylene and butene, useful crystalline polymers cannot be obtained unless alkyl groups such as methyl and ethyl groups are sterically controlled to form an isotactic structure. As in the case of polymerization, simply improving the activity does not result in a useful polymerization catalyst, and controlling the stereoregularity of the resulting polymer is a major issue. Regarding this problem, a method has been proposed in which the stereoregularity of the resulting polymer is improved by adding an electron-donating compound as a third component to a catalyst consisting of a carrier-type titanium component in which a titanium compound is supported on magnesium halide and an organoaluminum compound. has been done. For example, in the method of JP-A-52-100596, a composition obtained by co-pulverizing a magnesium halide, an organic acid ester, and an organosilicon compound is reacted with a titanium halide, an organoaluminium, and an organic acid. Catalysts consisting of esters have been proposed. Furthermore, Japanese Patent Publication No. 7318/1983 proposed a catalyst comprising a carrier-type titanium component, a trialkylaluminium, a Lewis base, and further a halogen-containing organoaluminum compound. An object of the present invention is to provide a catalyst which provides a poly-α-olefin with higher activity and crystallinity than those obtained by these methods. The present inventors investigated various catalysts and found that (A) active titanium compounds, (B) trialkyl aluminum, (C) silicon compounds, and (D) organic sulfuric acid represented by the general formula Al ₂ R ¹ ₄ SO ₄ . discovered that a catalyst consisting of an aluminum compound gave very good results,
This led to the present invention. The active titanium compound (A) of the present invention includes a known complex which essentially contains at least magnesium, halogen, trivalent or tetravalent titanium, and an electron-donating compound. Regarding the ratio of each component of the active titanium compound, for example, the molar ratio of magnesium to titanium is usually 3-40, preferably 10-30. The molar ratio of the electron donating compound to titanium is 0.1 or more, preferably 0.3-6. This active titanium component is obtained by, for example, pulverizing magnesium halide or dialkoxymagnesium and an electron-donating compound, treating it with liquid titanium tetrahalide, and then using the resulting solid component in an inert solvent such as n-heptane. Obtained by washing with It can also be obtained by grinding a complex of an electron donating compound and titanium halide with magnesium halide. The electron-donating compounds used here include amines, amides, ethers, ketones, nitriles, phosphines, phosphoramides, esters, thioethers, thioesters, acid anhydrides, acid halides, aldehydes, alcoholates, organic acids, silicon-containing compounds, periodic Examples include amides and salts of metals belonging to Groups 1 to 4 of the Table of Contents,
Among these, esters, ethers, silicon-containing compounds, and diamines are preferred. Component (B) of the present invention includes trialkylaluminum such as triethylaluminum, trimethylaluminum, tri-n-propylaluminum, triisobutylaluminum, or a mixture thereof, or a trialkylaluminum compound and water according to a known method, Compounds obtained by reaction with ammonia or _primary amines, such as _{( C2H5} ) _2Al -O-Al( _C2H5 ) ₂ ,

[Formula] etc. The component (C) of the present invention has the general formula Si(OR ² ) ₄ or Si(OR ³ ) _l R ⁴ _n X _o (wherein R ² , R ³ , and R ⁴ are 1-12
Hydrocarbon residue having a carbon atom, X is a halogen atom or a carbonyloxy group, o≦l≦4, o≦m
≦4, o≦n≦4 and l+m+n=4), specifically Si(OC ₂ H ₅ ) ₄ , Si
(C ₂ H ₅ ) (OC ₂ H ₅ ) ₃ , Si (C ₂ H ₅ ) ₂ (OC ₂ H ₅ ) ₃ , Si
(C ₂ H ₅ ) ₂ (OC ₂ H ₅ ) ₂ , Si (CH ₃ ) (OCOCH ₃ ) ₃ , Si
(OC ₂ H ₅ ) ₃ Cl, among others, Si
(OC ₂ H ₅ ) ₄ , Si(C ₂ H ₅ ) ₂ (OC ₂ H ₅ ) ₂ , Si(C ₂ H ₅ )
(OC ₂ H ₅ ) ₃ , Si(C ₆ H ₅ )(OC ₂ H ₅ ) ₃ and the like are preferred. Component (D) of the present invention is represented by the general formula Al ₂ R ¹ ₄ SO ₄ (wherein R ¹ represents an alkyl group having 1-12 carbon atoms, and the R ¹ groups are the same or different). compound, specifically Al ₂
(C ₂ H ₅ ) ₄ SO ₄ , Al ₂ (i−C ₃ H ₇ ) ₄ SO ₄ , Al ₂
(C ₆ H ₅ ) ₄ SO ₄ and the like. The polymerization method of the present invention is characterized in that components (A), (B), (C), and (D) are present together in the presence of (A), (B), (C), and (D). ) can be mixed in any order; for example, a method in which four components (A), (B), (C), and (D) are mixed simultaneously; Method of mixing A), mixing (B) and (D), then mixing (C), and then
A method such as mixing (A) can be adopted.
The amount of component (C) added is 0.1 per titanium atom in component (A).
Component (B) is preferably 1 to 100 mol per titanium atom in component (A), and component (D) is preferably 1 to 100 mol per titanium atom in component (A). The α-olefins used in the polymerization method of the present invention include propylene, 1-butene, 4-methyl-1-
These include pentene and 1-octene, and these can be homopolymerized, copolymerized with each other, or copolymerized with ethylene. In copolymerization, polyunsaturated compounds such as conjugated dienes and non-conjugated dienes can be selected as copolymerization components. Polymerization can be carried out in either liquid phase or gas phase. When carrying out liquid phase polymerization, an inert solvent such as hexane, heptane or kerosene may be used as the reaction medium, but the liquefied olefin itself may also be used as the reaction medium. The polymerization temperature of α-olefin is generally in the range of 0-100°C, preferably 20-90°C, and the polymerization pressure is normal pressure -50 atmospheres, preferably normal pressure -
It is in the range of 40 atmospheres. The molecular weight of the polymer produced in the method of the present invention varies depending on the reaction mode, catalyst, and polymerization conditions, but can be controlled by adding hydrogen, alkyl halide, dialkylzinc, etc., if necessary. By using the method of the present invention, highly crystalline poly-α-olefin can be produced in high yield per catalyst without substantially requiring a step to remove amorphous poly-α-olefin that adversely affects the physical properties of the polymer. can be obtained and has very high practical value. Example 1 A vibratory mill equipped with a grinding pot having an internal volume of 600 ml and containing 80 steel balls with a diameter of 12 mm was prepared. In this pot, add 20% magnesium chloride in a nitrogen atmosphere.
g 4 ml of tetraethoxysilane and 3 ml of α・α・α-trichlorotoluene were added and pulverized for 40 hours. 200
Add 10 g of the above pulverized product and 50 ml of titanium tetrachloride to a ml round bottom flask, stir at 80°C for 2 hours, remove the supernatant liquid by decantation, then add 100 ml of n-heptane and stir at 30°C. After stirring for 15 minutes, a washing operation in which the supernatant liquid was removed by decantation was repeated seven times, and then 100 ml of n-heptane was added to obtain an activated titanium component slurry. When a part of this activated titanium component slurry was sampled, n-heptane was evaporated, and analyzed, it was found that the activated titanium component contained 1.71 wt% Ti. Internal volume 3
n-heptane 1 102 mg of the above activated titanium component in a SUS-32 autoclave under nitrogen atmosphere,
Triethyl aluminum 0.12ml, Al ₂
( _C2H5 ) _{4SO4 76mg ,} tetraethoxysilane 0.09ml
was loaded. After the nitrogen in the autoclave was evacuated using a vacuum pump, hydrogen was charged at a gas phase partial pressure of 0.2 kg/cm ² , and then propylene was charged to bring the pressure in the gas phase to 2 kg/cm ² gauge. Heat the contents of the autoclave and increase the internal temperature to 70℃ after 5 minutes.
Polymerization was continued for 2 hours while charging propylene to maintain the polymerization pressure at 5 Kg/cm ² gauge. After cooling the autoclave, unreacted propylene was purged and the contents were taken out, filtered, and dried under reduced pressure at 60°C to obtain 262.5 g of white powder polypropylene. With this polypropylene boiling n-heptane
The proportion of residual polymer after 10 hours of extraction (hereinafter abbreviated as powder) is 98.2%, bulk specific gravity 0.34g/
The cc intrinsic viscosity number (measured with tetralin liquid at 135°C, same as below) was 1.82. On the other hand, 4.0 g of n-heptane soluble polymer was obtained by concentrating the liquid. The ratio of the boiling n-heptine extraction residue polymer to the total polymer (hereinafter abbreviated as total) was 96.7%.
In addition, the polymerization activity of the catalyst in the polymerization reaction is 76.8Kg/g-
It was Ti・hr. Comparative Example 1 100.2 mg of the active titanium component of Example 1, 0.12 ml of triethylaluminum, and tetraethoxysilane
Polymerization was carried out in the same manner as in Example 1, except that 0.09 ml was used. The results are shown in Table 2. Comparative Example 2 110.5 mg of the active titanium component of Example 1, 0.12 ml of triethylaluminum, and tetraethoxysilane
0.09ml, diethyl aluminum chlorate 0.07ml
Polymerization was carried out in the same manner as in Example 1, except that . The results are shown in Table 2. Comparative Example 3 115.5 mg of the active titanium component of Example 1, 0.12 ml of triethylaluminum, and tetraethoxysilane
0.09ml, diethylaluminum sesquichloride
Polymerization was carried out in the same manner as in Example 1, except that 0.07 ml was used. The results are shown in Table 2. Examples 2 to 4 (B), (C), (D) using the active titanium component of Example 1
Polymerization was carried out in the same manner as in Example 1, except that the components shown in Table 1 were used. The results are shown in Table 1. Example 5 68.2 mg of the active titanium component of Example 1 was placed in an autoclave No. 5 that had been thoroughly dried and purged with nitrogen.
Components (B), (C), and (D) were charged in the amounts shown in Table 1, the autoclave was replaced with propylene gas, 1.5Kg of liquid propylene was charged, and 3.9N of hydrogen was charged.
The temperature of the autoclave was raised to 75°C while stirring, and the temperature was kept at 75°C for 2 hours. After the polymerization was completed, unreacted propylene was purged and the contents were taken out.
The results are shown in Table 1.

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Claims (1)

[Scope of Claims] 1 (A) Magnesium halide or dialkoxymagnesium and an electron-donating compound are pulverized and treated with liquid titanium tetrachloride, or a complex of an electron-donating compound and titanium halide is obtained. (B) triallykyl aluminum compounds or organoaluminum compounds having two or more aluminum atoms bonded to each other by oxygen or nitrogen atoms; C) silicon compound, and (D) general formula Al ₂ R ¹ ₄ SO ₄ (However, R ¹ represents an alkyl group having 1 to 12 carbon atoms, and the four R ^1s may be the same or different.) A method for producing a polyα-olefin having stereoregularity, characterized by using a catalyst containing both an organoaluminum compound represented by the following. 2 The electronic compound is an amine, amide, aldehyde, alcoholate, ether, ester, silicon-containing compound, ketone, acid halide, acid anhydride, thioether, thioester, nitrile, phosphine, phosphoramide, organic acid, and periodic table The manufacturing method according to claim 1, wherein the compound is one or more compounds selected from amides or salts of metals belonging to Groups 1 to 4. 3 The silicon compound (C) is represented by the general formula Si(OR ² ) ₄ (However, R ² is a hydrocarbon group having 1 to 12 carbon atoms, and the four R ² may be the same or different.) Silicate ester, or general formula Si(OR ³ ) _l R ⁴ _n X _o (However, R ³ and R ⁴ are hydrocarbon groups having 1 to 12 carbon atoms,
Including cases where they are the same or different from each other. X is a halogen atom or a carbonyloxy group, l,
m and n are 0≦l<4, 0≦m≦4, 0≦n<4, and l+m+n=4. ) The manufacturing method according to claim 1 or 2, which is an organoalkoxysilane represented by: