JPS619408A - Production of olefin polymer - Google Patents

Abstract

PURPOSE:To obtain an odorless, highly reactive and highly stereoregular olefin polymer in high yields, by polymerizing an olefin by using a catalyst system formed by combining a specified solid catalyst component with an organoaluminum compound and an organic peroxide. CONSTITUTION:An olefin is polymerized by contact with a catalyst system formed by combining a solid catalyst component comprising a magnesium halide and a titanium halide, an organoaluminum compound, and an organic peroxide of the formula (wherein R1-R3 are each a saturated or unsaturated hydrocarbon group, and R4 is an oxygen-containing or oxygen-free hydrocarbon group). The magnesium halide used is preferably magnesium chloride, preferably anhydrous. The titanium halide is preferably a chloride, particularly preferably titanium tetrachloride. Examples of the compounds of the formula include dicumyl peroxide and bis(1,1-diphenylethyl)peroxide.

Description

BACKGROUND OF THE INVENTION TECHNICAL FIELD The present invention relates to a process for producing olefin polymers. More specifically, the present invention relates to a method for producing an olefin polymer that can yield a highly stereoregular polymer in high yield when applied to the polymerization of an α-olefin having 3 or more carbon atoms.

Prior Art Until now, catalyst systems consisting of a solid catalyst component in which a titanium compound is supported on magnesium halide and an organoaluminum compound have higher polymerization activity than conventional catalyst systems.
It has been suggested that the need to remove catalyst residues from polymers may be eliminated.

However, this supported catalyst has low stereoregularity, and it has been considered impossible to omit the extraction step of the atactic polymer. However, in recent years, improvements in the cocatalyst system have resulted in significantly improved stereoregularity. It has been. For example, as polymerization additives, esters (Japanese Patent Publication No. 56-39767, JP-A-58-157808, etc.), organosilicon compounds (% JP-A-57-63311, JP-A-58-83006, etc.) are used as polymerization additives.
It is known that polymerization with a certain degree of high activity and high stereoregularity is possible by using polymers with high activity and high stereoregularity. However, the present inventors believe that these proposed polymerization additives have problems such as being odorous or expensive, and also have insufficient polymerization performance.

Summary The present inventors have therefore been actively searching for a novel monopolymer additive in order to realize highly active and highly stereoregular polymerization using an odorless and inexpensive polymerization additive. As a result, by using an organic peroxide with a specific structure, highly active and highly stereoregular polymerization was realized, and the present invention was achieved.

-1 That is, the method for producing an olefin polymer according to the present invention c.
The olefin is combined with (5) a solid catalyst component containing magnesium halide and titanium halide as essential components, (Bl
The method is characterized in that it is brought into contact with a catalyst system comprising a combination of an organoaluminum compound and an organic peroxide represented by the following formula (q) for polymerization.

R2-C-0-0-R4 (In the formula, R1% R3 is a saturated or unsaturated hydrocarbon group, and R4 is a hydrocarbon group containing or not containing an oxygen atom.) Effect of this specific organic peroxide When used as one of the catalyst components, odorless, highly stereoregular olefin polymers can be obtained in high yields.

DETAILED DESCRIPTION OF THE INVENTION Catalyst System The catalyst system according to the invention is a combination of specific components (5), (B) and (C).

Solid Catalyst Component The solid catalyst component (5) used in the present invention contains magnesium halide and titanium halide as essential components.

Magnesium halides include magnesium chloride,
Magnesium bromide and magnesium iodide can be used. Preferably it is magnesium chloride, and it is further desirable that it be substantially anhydrous.

As the titanium halide, titanium chloride, bromide and iodide can be used. Chlorides are preferred, and examples include titanium tetrachloride and titanium trichloride, with titanium tetrachloride being particularly preferred.

Further, an alkoxy group-containing titanium compound (for example, titanium tetrabutoxide) represented by the general formula Ti (OR) nCl a-n (R is an alkyl group) can also be used.

The solid catalyst component (Al essentially contains the above-mentioned nyl compound, but it may also contain an electron donor compound, which is also preferable. compounds and nitrogen-containing compounds.

As the oxygen-containing compound, ethers, ketones, and esters can be used, but esters are preferably used.

As esters, carboxylic acid esters are mainly used, and as aliphatic carboxylic esters, lower mono- or dialcohols of lower mono- or dicarboxylic acids (in the case of dialcohols, one hydroxyl group is etherified with a lower alkyl) Specific examples include ethyl acetate, meglucerosolve acetate, ethyl seronulp acetate, methyl methacrylate, diethyl oxalate, dibutyl maleate, and the like. Examples of aromatic carboxylic acid esters include ethyl benzoate, methyl p-toluate, diethyl phthalate, and diheptyl phthalate. Particularly preferred among these esters are -diethyl phthalate, dihexyl phthalate, etc.
It is a tarric acid ester.

In preparing the solid catalyst component (5), it is desirable to first pre-treat magnesium chloride. This can be carried out using pulverization or dissolution/precipitation techniques. Magnesium chloride can be pulverized using a ball mill or a vibration mill. Can magnesium chloride be dissolved using a hydrocarbon or halogenated hydrocarbon as a solvent? J M It can be carried out using an alcohol, a phosphoric acid ester, or a titanium alkoxide (for example, titanium tetrabutoxide) as a promoter. Precipitation of dissolved magnesium chloride is caused by poor solvents, inorganic halides, methylhydrodiene polysiloxane,
Alternatively, it can be carried out by adding an electron donor such as an ester. For details of such a pretreatment for activation of magnesium chloride, see JP-A-53-45688.

Reference may be made to Publications No. 54-31092, No. 57-180612, Kokai No. 5309, and No. 58-5310.

The order of contact between activated magnesium chloride, titanium halide, and, if necessary, an electron donor may be such that a complex of titanium halide and an electron donor is formed, and then this complex is brought into contact with magnesium chloride. Alternatively, magnesium chloride and titanium halide may be brought into contact with each other and then brought into contact with an electron donor. Alternatively, a method may be used in which magnesium chloride is brought into contact with an electron donor and then brought into contact with titanium halide.

The contact may be carried out by pulverization using a ball mill, vibration mill, or the like, or by adding magnesium chloride or an electron donor-treated product of magnesium chloride to the liquid phase of titanium halide.

After contacting two or three components or at an intermediate stage between contacting each component,
Washing with an inert solvent may also be performed.

The titanium halide content of the solid catalyst component thus produced is 1-20% by weight, and the molar ratio of electron donor to titanium halide is 0.05-2.0.

Organoaluminum compounds However, the organoaluminum compounds used in the present invention include:
Trialkylaluminum is preferred.

Examples include trimethylaluminum, triethylaluminum, )lJi-7'tilaluminum, tri-n-hexylaluminum, and the like. Particularly preferred is triethylaluminum.

Moreover, organic aluminum compounds such as alkyl aluminum halides and alkyl aluminum alkoxides can also be used in combination.

The molar ratio of the organoaluminum compound (Bl) used in the polymerization to constitute the catalyst system of the present invention and the titanium halide in the solid catalyst component (5) is usually in the range of 10 to 1000.

Organic peroxide (C) The organic peroxide used in the present invention is a compound represented by the following formula.

(In the formula, + Rt to R4 are saturated or unsaturated hydrocarbon groups, and R4 is a hydrocarbon group containing or not containing an oxygen atom.) Specific examples of R1 to R4 include groups having about 1 to 20 carbon atoms. It is an aliphatic or aromatic hydrocarbon. Specific example of R4-R1~
Hydrocarbons as mentioned as specific examples of R4 and ether oxygen or carbonyl oxygen introduced therein.

Specific examples of such compounds include 1,1-bis(tert-butylperoxy)3,3,5-)limethylcyclohexane, 1,1-bis(tert-butylperoxy)cyclohexane, di-tert-butylperoxy Butyl peroxide, tert-butyl cumyl peroxide, dicumyl peroxide, bis(1,1-diphenylethyl) peroxide, 2,5-
Examples include dimethyl-2,5-di(tert-butylperoxy)hexane. Preferred are dicumyl peroxide and bis(1,1-diphenylethyl) peroxide.

The molar ratio of the organic peroxide (C) and the organoaluminum compound (B) used is usually 0.01 to 1.0, preferably 0.02 to 0.5.

The catalyst system of the present invention is suitably used in the homopolymerization of ethylene, propylene, and butene, or in the copolymerization of a combination of these monomers.

The polymerization can be carried out in the presence or absence of an inert solvent, ie bulk polymerization in the gas or liquid phase. The polymerization mode may be continuous or batchwise. The molecular weight of the polymer can be adjusted by controlling the hydrogen concentration in the polymerization tank. The overlapping temperature is 0 to 200°C, preferably 50 to 10°C.
A range of 0°C is chosen. The polymerization pressure is selected from a range of 1 to 100 atm.

Experimental Examples Example 1 75 ml of purified hebutane,
75 of titanium tetrabutoxide and 102 of anhydrous magnesium chloride are added. Thereafter, the temperature of the flask is raised to 90° C., and the magnesium chloride is completely dissolved over a period of 2 hours. Next, the flask is cooled to 40° C. and methylhydrodienepolysiloxane 15- is added to precipitate the magnesium chloride/titanium tetrabutoxide complex.

After washing this with butane, silicon tetrachloride 8
, 7- and dihebutyl phthalate 1.8-.

Hold at ℃ for 2 hours. After this, the purified hexafluoride was washed with butane, and further titanium tetrachloride 25- was added, and the mixture was heated at 90°C for 2
Hold time. This was washed with purified butane to obtain a solid catalyst component.

The titanium content in the solid catalyst component (5) was 3.0% by weight, and the diheptyl phthalate content was 5.0% by weight.

(2) A stainless steel t-tox tube with a polymerization internal volume of 3 liters was replaced with nitrogen, and 1.5 liters of purified hebutane, triethylaluminum (BIO, 75F, dicumyl peroxide (?10.1M and The above solid catalyst component (4) 50q
and hydrogen in an amount corresponding to a partial pressure of 0.15' Kg/ct.

Then, after raising the temperature of the autoclave to 70°C, the pressure of propylene was increased to 7 kg/d G to start polymerization, and the polymerization was continued for 3 hours while replenishing propylene to maintain this pressure. After 3 hours, Polymerization was stopped by stopping the introduction of monomers and purging unreacted monomers.

When the produced polymer was separated from heptane and dried, 7
．． 53.6 f of polypropylene powder was obtained.

When heptane was removed from the p liquid by heating, an amorphous polymer of 5.32% was obtained. The proportion of amorphous polymer in the total polymer (hereinafter referred to as APP by-product rate) was 0.70%.

In addition, boiling n-hebutane insoluble content of polypropylene powder (
Hereinafter referred to as P-II) was 96.3%. The polymer yield per solid catalyst (hereinafter referred to as CY and abbreviated as "f") is 151
It was 78. MFR (melt flow index: A
Measured according to STM-D-1238. ) is 2,10
, the bulk specific gravity was 0.46.

The polypropylene powder obtained was completely odorless.

Example 2 The solid catalyst component (5) was prepared in the same manner as in Example 1, except that di-tert-butyl peroxide 0.096F was used as the polymerization additive (C) in the dicumyl peroxide solution. Polymerization was carried out in the same manner as in Example 1.

As a result, 613.49% polypropylene powder was obtained, and the APP by-product rate was 2.57%. P-II is 90
．． 6%, CY was 12592, MFRti6.55-bulk specific gravity was 0.43. The obtained polypropylene powder was completely odorless.

Example 3 In polymerization, the amount of dicumyl peroxide added was 0.3
The same experiment as in Example 1 was conducted except that the temperature was set to 49.

As a result, 713.49% polypropylene powder was obtained, and the APP by-product rate was 0.65%. P-II is 97
．． 5%, CY was 14361, MFR was 1.95, and bulk specific gravity was 0.47. The polypropylene powder obtained was completely odorless.

Example 4 In polymerization, the amount of dicumyl peroxide added was 0.0
The same experiment as in Example 1 was conducted except that the temperature was 9f.

As a result, borifuropyrene powder of 776.4% was obtained, and the APP by-product rate was 0.75%. P-II is 95.8%, CY is 15645- MFR is 2.21
The bulk specific gravity was 0.46. The resulting polypropylene powder was completely odorless.

Applicant's agent: Boar, written amendment of clearing procedure 1985, 91st day Special V1 Agency Director Michibu Uga 1 Display of incident 1981 Patent Application No. 130385 2 Name of the invention Method for producing A-refin polymer 3 Person making the amendment Relationship to the case Patent applicant (605) Mitsubishi Yuka Co., Ltd. 4th generation scientist 3-2-3 Marunouchi, Chiyoda-ku, Tokyo Telephone Tokyo (211) 2321 representative “Detailed description of the invention” shelf in the specification 8 Contents of amendment Add the following ten sentences after the third line of page 15 of Mei 111 River.

[Example 5 Preparation of solid catalyst component 75 ml of purified hebutane, 75 ml of titanate 1-rhabdoxide and 10
Add tj of anhydrous magnesium chloride. Thereafter, the temperature of the flask was raised to 90°C, and the magnesium chloride was completely dissolved over a period of 2 hours. Next, the flask '-1 was cooled to 40°C, and 15 ml of methyl hyde
By adding , a magnesium chloride/titanium tetrabutoxide complex is precipitated. After washing the mixture with butane, 6.7 m+ of silicon tetrachloride and 1.51111 l of chloride were added and kept at 50°C for 2 hours.

After this attack, the titanium tetrachloride was washed with purified hebutane, and titanium tetrachloride
Add 5ml and keep at 30°C for 2 hours.

This was washed with titanium manufactured by fi'I to obtain a solid catalyst component.

The titanium content in the solid catalyst component was 3.3% by weight, and the specific surface area of the solid catalyst component was 1.2 Wt/g.

polymerization

Claims (1)

[Scope of Claims] Olefins are combined into (A) a solid catalyst component containing magnesium halide and titanium halide, (B)
) A method for producing an olefin polymer, which comprises polymerizing it by contacting it with a catalyst system comprising a combination of an organoaluminum compound and (C) an organic peroxide represented by the following formula. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, R_1 to R_3 are saturated or unsaturated hydrocarbon groups, and R_4 is a hydrocarbon group containing or not containing an oxygen atom.)