JPH07657B2 - Method for producing cylindrical polyolefin - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a polyolefin having a special shape, and particularly to a method for producing a cylindrical polyolefin.

[Conventional technology]

Conventionally, in polyolefins such as polyethylene and polypropylene, many varieties having various characteristics have been developed.

However, in recent years, there has been an increasing demand for polyolefin having superior new properties.

Further, in the conventional technique, in order to impart a special property or form to polyolefin, it is necessary to add a special substance to the polymer obtained by once polymerizing, and to mold it using a special molding machine. It was. However, these methods require an extra process, which causes a cost increase of the product.

[Problems to be Solved by the Invention] The present inventors arrived at the present invention as a result of conducting research for the purpose of obtaining a polyolefin having new properties from such a viewpoint by a simpler method, that is, only a polymerization operation. ,
This is what we propose here.

[Means for solving problems]

That is, a feature of the present invention is that (a) basic magnesium carbonate and (b) a magnesium compound obtained by reacting magnesium metal with a halogenated hydrocarbon (hereinafter abbreviated as "magnesium compound"). ,
(C) An organic compound represented by the general formula R ¹ OR ² (wherein R ¹ and R ² are an alkyl group or an aryl group, and may be the same or different), hereinafter referred to simply as an ether. Abbreviated as a kind.)
(D) by contacting with a diester of an aromatic dicarboxylic acid and (e) a titanium halide represented by the general formula TiX ₄ (where X represents a halogen element) (hereinafter abbreviated as “titanium halide”). Another object of the present invention is to provide a method for producing a cylindrical polyolefin, which comprises polymerizing olefin in the presence of a catalyst containing the obtained catalyst component and an organoaluminum compound. Polymerization here means homopolymerization and copolymerization.

The basic magnesium carbonate used in the present invention is
A commercially available product can be appropriately selected.

The magnesium compound used in the present invention needs to be a compound obtained by reacting metallic magnesium with a halogenated hydrocarbon. If necessary, the preparation of the magnesium compound in the present invention is carried out by reacting metallic magnesium and a halogenated hydrocarbon in the presence of iodine or an iodine compound at a temperature substantially from 0 ° C. to the boiling point of the halogenated hydrocarbon used. Is preferably carried out until completion.

As the organic compound represented by the general formula R ¹ OR ² used in the present invention, various ethers are preferable, and aliphatic ethers are particularly preferable.

The diester of aromatic dicarboxylic acid used in the present invention is preferably a diester of phthalic acid or terephthalic acid, for example, dimethyl phthalate, dimethyl terephthalate, diethyl phthalate, diethyl terephthalate, dipropyl phthalate, dipropyl terephthalate, dibutyl phthalate, dibutyl. Examples thereof include terephthalate, diisobutylphthalate, diamylphthalate, diisoamylphthalate, ethylbutylphthalate, ethylisobutylphthalate and ethylpropylphthalate.

The halogenated hydrocarbon used in the present invention is preferably a chloride of an aliphatic hydrocarbon which is liquid at room temperature.

The titanium halide used in the present invention is
TiCl ₄ , TiBr ₄ , TiI _{4 and the} like can be mentioned, but TiCl ₄ is particularly preferable.

When obtaining the catalyst component of the present invention, the use ratio of each raw material constituting the catalyst component is optional, and is not particularly limited, as long as it does not adversely affect the performance of the produced catalyst component. Normally, 1g of basic magnesium carbonate,
The magnesium compound is used in an amount of 0.1 g or more, preferably 0.5 g or more, and if the amount is 0.1 g or less, it is not preferable because the catalytic activity decreases.

The ethers are used in the range of 1 ml or more per 1 g of the total of the basic magnesium carbonate and the magnesium compound. Further, the diester of aromatic dicarboxylic acid is used in the range of 0.01 to 1 g, preferably 0.05 to 1 g, based on 1 g of the total of the basic magnesium carbonate and the magnesium compound,
The titanium halide is used in an amount of 0.1 g or more, preferably 1.0 g or more based on 1 g of the total of the basic magnesium carbonate and the magnesium compound.

In obtaining the catalyst component used in the present invention, after contacting basic magnesium carbonate and the magnesium compound in the ethers, excess ethers are dried under reduced pressure and removed by a method such as excess. It is then preferred to contact the diester of an aromatic dicarboxylic acid with a titanium halide. At this time, the contact between the basic magnesium carbonate and the magnesium compound in the ethers is preferably carried out at a temperature from 0 ° C. to the boiling point of the ethers usually used, and the aromatic dicarboxylic acid to be subsequently used. The contact with the diester and the titanium halide is usually carried out at a temperature from 0 ° C. to the boiling point of the titanium halide used for 5 minutes or longer, preferably 10 minutes or longer.

The composition obtained after the contact can be repeatedly contacted with a titanium halide, or can be washed with an organic solvent such as n-heptane.

It is preferable that these series of operations in the present invention are performed in the absence of oxygen and water.

The catalyst component produced as described above is combined with an organoaluminum compound to form a catalyst for producing a cylindrical polyolefin. The organoaluminum compound used is used in a molar ratio of 1 to 1000 per mole of titanium atom in the catalyst component. Further, addition and use of a third component such as an electron-donating substance during polymerization are not hindered.

In particular, when an organosilicon compound containing an oxygen atom is added, a cylindrical polyolefin having an extremely high stereoregularity while maintaining an extremely high activity can be obtained. Further, the catalyst component in the present invention does not require a deashing step or the like because the chlorine content in the component is extremely low, and thus can be put to practical use without reducing the characteristics of the cylindrical polyolefin.

The polymerization can be carried out in the presence or absence of an organic solvent, and the olefin monomer can be used in either gas or liquid state. Polymerization temperature is 200
℃ or less preferably 100 ℃ or less, the polymerization pressure is 100kg / c
m ² · G or less, preferably 50 kg / cm ² · G or less.

The olefins homopolymerized or copolymerized using the catalyst of the present invention are ethylene, propylene, 1-butene and the like.

〔The invention's effect〕

According to the present invention, an extremely high polymerization activity and stereoregularity can be obtained without any additional treatment such as addition of a special substance to a polymer obtained by polymerization and molding of the polymer by a special molding machine. While maintaining the above, a cylindrical polyolefin can be obtained by only one-step polymerization operation. Since the cylindrical polyolefin obtained according to the present invention has an extremely low chlorine content in the catalyst component according to the present invention, it is expected to have a wide range of uses such as various composite materials without requiring an operation such as deashing. .

〔Example〕

 The present invention will be specifically described below with reference to examples.

Example 1 [Preparation of Magnesium Compound] The capacity was 2.0 l, which was sufficiently replaced with nitrogen gas and equipped with a stirrer.
30 g of magnesium powder, 1.0 g of iodine and 1.2 l of n-butyl chloride were placed in the round-bottomed flask described in (1) and reacted at the boiling point of n-butyl chloride for 5 hours. After the completion of the reaction, the supernatant was removed, the mixture was washed with 500 ml of n-butyl chloride three times, and then dried under reduced pressure to obtain a powdery magnesium compound.

[Adjustment of catalyst component]

Fully replaced by nitrogen gas, equipped with a stirrer, capacity 500m
10 g of the magnesium compound obtained as described above, 6.0 g of basic magnesium carbonate and 100 ml of diethyl ether were placed in a round-bottomed flask having a volume of 1 and reacted for 2 hours at the boiling point of diethyl ether. After completion of the reaction, the supernatant was removed and dried under reduced pressure to obtain a solid composition.

Fully replaced by nitrogen gas, equipped with a stirrer, capacity 500m
5 g of the solid composition, 1.0 ml of dibutyl phthalate and 200 ml of TiCl ₄ were placed in a 1-liter round bottom flask and the temperature was raised to 120 ° C. for reaction for 2 hours. After the reaction was completed, the supernatant was removed and a new Ti
200 ml of Cl ₄ was added and reacted at 120 ° C. for 2 hours.

After completion of the reaction, the mixture was cooled to 40 ° C and washed 10 times with 200 ml of n-heptane to obtain a catalyst component. At this time, when the solid-liquid of the catalyst component was separated and the titanium content of the solid was measured, 2.
It was 91% by weight.

〔polymerization〕

To an autoclave with a stirrer having an internal volume of 2.0 l which was completely replaced with nitrogen gas, 700 ml of n-heptane was charged, and 301 mg of triethylaluminum, 32 mg of phenyltriethoxysilane while maintaining the nitrogen gas atmosphere, and then the catalyst components were added. 0.5 mg of titanium atom was charged. After that, 150 ml of hydrogen gas was charged, the temperature was raised to 70 ° C, and propylene gas was introduced while 6 kg /
Polymerization was carried out for 4 hours while maintaining the pressure of cm ² · G. After the completion of the polymerization, the solid polymer obtained was separated, heated at 80 ° C. and dried under reduced pressure to obtain 302 g of a colorless and transparent columnar polymer having a length of about 1 to 2 mm. Meanwhile, the liquid was condensed to obtain 6.1 g of a polymer. The MI of the columnar polymer was 6.1.

Example 2 An experiment was conducted in the same manner as in Example 1 except that dipropyl phthalate was used instead of dibutyl phthalate. The titanium content in the solid content at this time was 3.16% by weight. When the polymerization was conducted in the same manner as in Example 1, 290 g of a colorless and transparent columnar polymer having a length of about 1 to 2 mm was obtained. Meanwhile, the liquid was condensed to obtain 5.9 g of a polymer. The MI of the columnar polymer was 7.8.

[Brief description of drawings]

FIG. 1 is a flow chart for explaining the present invention.

Claims (1)

[Claims] 1. (a) Basic magnesium carbonate, and (b)
A magnesium compound obtained by reacting metallic magnesium with a halogenated hydrocarbon is (c) represented by the general formula R ¹ OR
² (wherein R ¹ and R ² are an alkyl group or an aryl group) is contacted in an organic compound represented by
(D) A diester of an aromatic dicarboxylic acid and (e) a catalyst component obtained by contacting with a titanium halide represented by the general formula TiX ₄ (wherein X represents a halogen element), and an organoaluminum compound. In the presence of a catalyst,
A method for producing a cylindrical polyolefin, comprising polymerizing olefins.