JPH0699504B2 - 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 columnar polyolefin.

[Conventional technology]

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

However, in recent years, the demand for polyolefins having more excellent new properties has increased.

Further, in the conventional technology, in order to impart a special property or morphology to the polyolefin, it is necessary to add a special substance to the polymer once obtained by polymerization, and to mold it using a special molding machine. Met. However, since these methods require extra steps, they have increased the cost of the product.

[Problems to be Solved by the Invention] The present inventors have reached 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 magnesium compound obtained by reacting (a) calcium carbonate, (b) metallic magnesium, and a halogenated hydrocarbon (hereinafter simply referred to as “magnesium compound”). is there.)
And (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 simply referred to as Abbreviated as ethers.)
(D) A diester of an aromatic dicarboxylic acid and (e) a titanium halide represented by the general formula TiX ₄ (wherein X is a halogen element) (hereinafter sometimes simply referred to as "titanium halide"). Another object of the present invention is to provide a method for producing a columnar polyolefin, which comprises polymerizing an olefin in the presence of a catalyst containing a catalyst component obtained by contacting with an organoaluminum compound. Polymerization here means homopolymerization and copolymerization.

As the calcium carbonate used in the present invention, 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. Usually, the magnesium compound is used in an amount of 0.1 g or more, preferably 0.5 g or more, relative to 1 g of calcium carbonate, and if the amount is 0.1 g or less, the catalytic activity is lowered, which is not preferable.

The ethers are used in an amount of 1 ml or more per 1 g of the total of calcium 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, relative to the total 1 g of calcium carbonate and the magnesium compound, and the titanium halide is the total of calcium carbonate and the magnesium compound. It is used in an amount of 0.1 g or more, preferably 1.0 g or more with respect to 1 g.

Incidentally, in obtaining the catalyst component used in the present invention, after the calcium carbonate and the magnesium compound are contacted in the ethers, excess ethers are removed by a method such as vacuum drying and filtration, Subsequent contact with a diester of an aromatic dicarboxylic acid and a titanium halide is preferred. At this time, the contact between the calcium carbonate and the magnesium compound in the ethers,
It is usually carried out at a temperature from 0 ° C. to the boiling point of the ether used, and the subsequent contact with a diester of an aromatic dicarboxylic acid and a titanium halide is usually carried out 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 may be repeatedly contacted with a titanium halide, or may 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 columnar polyolefin having extremely high stereoregularity can be obtained while maintaining extremely high activity. 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 columnar 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 a 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 columnar polyolefin can be obtained by only one-step polymerization operation. The columnar polyolefin obtained by the present invention does not require an operation such as deashing because the chlorine content in the catalyst component in the present invention is extremely low, and therefore is expected to have a wide range of applications such as various composite materials.

〔Example〕

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

Example 1 [Preparation of magnesium compound] Volume 2.0 fully replaced with nitrogen gas and equipped with a stirrer
In a round bottom flask, magnesium powder 30g, iodine 1.0g
And n-butyl chloride 1.2 were taken and reacted at the boiling point of n-butyl chloride for 5 hours. After the reaction,
The supernatant liquid was removed, washed three times with 500 ml of n-butyl chloride, and then dried under reduced pressure to obtain a magnesium compound in powder form.

[Adjustment of catalyst component]

Fully replaced by nitrogen gas, capacity 500m equipped with stirrer
10 g of the magnesium compound obtained as described above, 8.6 g of calcium 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, capacity 500m equipped with stirrer
5 g of the solid composition, 1.0 ml of dibutyl phthalate and 200 ml of TiCl ₄ were placed in a round bottom flask having a volume of 1, 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, the solid content of the catalyst component was separated and the titanium content of the solid content was measured.
It was 2.27% by weight.

[Overlap]

700 ml of n-heptane was charged into an autoclave with a stirrer and an internal volume of 2.0 which was completely replaced with nitrogen gas, and 301 mg of triethylaluminum was added while maintaining a nitrogen gas atmosphere.
32 mg of phenyltriethoxysilane and then 0.5 mg of the above catalyst component as titanium atoms were charged. Then hydrogen gas 150
While charging ml and raising the temperature to 70 ° C and introducing propylene gas
Polymerization was carried out for 4 hours while maintaining a pressure of 6 kg / cm ² · G. After completion of the polymerization, the solid polymer obtained was filtered, heated to 80 ° C. and dried under reduced pressure. On the other hand, the amount of the polymer dissolved in the polymerization solvent by condensing the filtrate is (A), and the amount of the solid polymer is (B). Further, the obtained solid polymer is extracted with boiling n-heptane for 6 hours to obtain a polymer insoluble in n-heptane, and this amount is designated as (C).

The polymerization activity (D) per catalyst component is calculated by the formula Express with.

Further, the yield (E) of the crystalline polymer is calculated by the formula The yield (F) of all crystalline polymer is expressed by I asked more. Residual chlorine (G) in the produced polymer and MI of the produced polymer are represented by (H). The obtained results are as shown in Table 1. The length of 1 to 2 mm due to the above polymerization
A colorless transparent cylindrical polymer was obtained.

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 2.68% by weight. An experiment was conducted in the same manner as in Example 1 during the polymerization. The results obtained are as shown in Table 1. In addition,
A colorless transparent columnar polymer having a length of about 1 to 2 mm was obtained by the above polymerization.

[Brief description of drawings]

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

Claims (1)

[Claims] 1. A magnesium compound obtained by reacting (a) calcium carbonate, (b) metallic magnesium and a halogenated hydrocarbon with (c) a general formula R ¹ OR ² (wherein R ¹
And R ² are alkyl groups or aryl groups and may be the same or different. ), And then contacting with (d) a diester of an aromatic dicarboxylic acid and (e) a titanium halide represented by the general formula TiX ₄ (where X is a halogen element). A method for producing a columnar polyolefin, which comprises polymerizing an olefin in the presence of a catalyst containing the catalyst component thus obtained and an organoaluminum compound.