JPH0670095B2 - Method for producing catalyst component for olefin polymerization - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention provides a catalyst component which, when subjected to the polymerization of olephins, has a high activity and is capable of obtaining a stereoregular polymer in a high yield. More particularly, it relates to a method for producing a catalyst component for olefin polymerization, which comprises contacting a solid composition obtained by pulverizing a magnesium compound and an electron donating substance at a low temperature with a titanium halide. It is a thing.

[Conventional technology]

Conventionally, solid titanium halides are well known and widely used as catalyst components for olefin polymerization.
Since the yield of the catalyst component and the polymer per titanium in the catalyst component (hereinafter simply referred to as the catalyst component and the polymerization activity per titanium in the catalyst component) is low, a so-called deashing step for removing the catalyst residue is unavoidable. It was. Since this deashing process uses a large amount of alcohol or a chelating agent, a recovery device or a regenerating device for them is indispensable, and there are many resources, energy, and other incidental problems, and a person skilled in the art can quickly solve them. This is an important issue that is desired. In order to eliminate this complicated deashing process, many studies have been made and proposed to increase the polymerization activity of the catalyst component, especially titanium per catalyst component.

In particular, as a recent tendency, when a transition metal compound such as titanium halide, which is an active ingredient, is supported on a carrier substance such as magnesium chloride and subjected to the polymerization of olefins, the polymerization activity per titanium in the catalyst component is significantly increased. There are many proposals to raise the price.

[Problems to be solved by the invention]

However, the conventionally proposed methods require very complicated steps such as dissolving magnesium chloride in alcohol, and while maintaining a high degree of stereoregular polymer yield with a simple method. No example can be found in which the polymerization activity per catalyst component is increased.

The present inventors have reached the present invention as a result of earnest research in order to solve the problems left over in the related art, and make a proactive proposal.

[Means for solving problems]

That is, the feature of the present invention is that (a) the general formula MgX ₂
A magnesium compound represented by the formula (wherein X is a halogen element), and (b) two kinds of electron-donating substances each selected from an aromatic carboxylic acid ester and a silicon compound having a Si—O bond. The solid composition obtained by pulverizing at a low temperature of 5 ° C. or lower is contacted with (c) a titanium halide represented by the general formula TiX ₄ (where X is a halogen element), and Another object of the present invention is to provide a method for producing a catalyst component for polymerization of olefins, which comprises contacting with a titanium halide.

Examples of the magnesium compound used in the present invention include magnesium fluoride, magnesium chloride, magnesium bromide, magnesium iodide, and the like. Among them, magnesium chloride is preferable.

The two types of electron-donating substances used in the present invention are selected from aromatic carboxylic acid esters and silicon compounds having a Si—O bond, respectively.

Examples of the titanium halide represented by the general formula TiX ₄ (where X is a halogen element) used in the present invention include TiCl ₄ , TiBr ₄ , TiI _{4 and the} like, among which TiCl ₄ is preferable.

After contacting the titanium halide with the solid composition produced in the present invention, it is necessary to further contact with the titanium halide, or the effect of the present invention can be obtained by washing with an organic solvent such as n-heptane. Can be increased.

The use ratio of each of these components is arbitrary as long as it does not adversely affect the performance of the produced catalyst component, and is not particularly limited, but usually the electron donating substance is 0.01 to 1 g per 1 g of the magnesium compound. Used at a rate of 1g.

The pulverization of the magnesium compound and two or more kinds of electron-donating substances in the present invention is usually carried out by a mechanical means, but a ball mill, a vibration mill, a tower grinder, an impact grinder, etc. are generally used. The crushing time varies depending on the performance of the apparatus used, but is usually in the range of 1 to 500 hours. Further, the pulverization temperature needs to be a low temperature of 5 ° C. or lower.

The contact between the titanium halide and the solid composition can be carried out by various methods, for example, in a vessel equipped with a stirrer, at a temperature range from room temperature to the boiling point of the titanium halide which is usually used. The contact time is arbitrary as long as the solid composition and titanium halide can be sufficiently contacted with each other, but is usually in the range of 10 minutes to 100 hours.

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

The catalyst component produced as described above is combined with an organoaluminum compound to form a catalyst for olefin polymerization.
The organoaluminum compound used is used in a range of 1 to 1000 in terms of molar ratio per mole of titanium atom in the catalyst component.
In addition, addition of a third component such as an electron-donating substance during the polymerization does not interfere.

The polymerization can be carried out in the presence or absence of an organic solvent. Further, the olefin monomer can be used in either a gas or liquid state. Polymerization temperature is 20
0 ℃ or less, preferably 100 ℃ or less, the polymerization pressure is 100kg /
cm ² · G or less, preferably 50 kg / cm ² · G or less.

Olefins homopolymerized or copolymerized using the catalyst component produced by the present invention are ethylene, propylene,
1-butene, 4-methyl-1-pentene and the like.

〔The invention's effect〕

When olefins are polymerized using the catalyst component obtained according to the present invention, the catalyst residue in the produced polymer can be kept extremely low due to its high activity, and thus the produced polymer can be The influence of chlorine exerted can be reduced. Further, it also shows an extremely excellent effect on the yield of the stereoregular polymer.

Further, in the conventionally known highly active supported catalyst, the activity was greatly reduced as the polymerization proceeded, and it was practically impossible to use it for copolymerization and the like, but it was obtained by the present invention. When such a catalyst component is used, such a phenomenon can be suppressed to a very low level and can be sufficiently used for copolymerization.

〔Example〕

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

Example 1 [Preparation of catalyst component] Magnesium chloride 30 g, phenyltriethoxysilane 3.8
ml and dipropyl phthalate 7.2 ml in a nitrogen gas atmosphere into a vibrating mill pot with a capacity of 1.0 filled with 25 mmφ stainless balls 4/5 of the total volume, and the frequency is 1430 v.p.
Milling was performed for 17 hours at −10 ° C. with a m and a swing of 3.5 mm.

Fully replaced by nitrogen gas, capacity 500m equipped with stirrer
200 ml of TiCl ₄ and 8 g of the solid composition obtained by the above-mentioned pulverization treatment were charged into a round-bottomed flask having a volume of 1 l, and stirred at 120 ° C. for 2 hours. After completion of the reaction, the mixture was left standing and the supernatant was removed by decantation, 200 ml of TiCl ₄ was newly added, and the mixture was stirred at 110 ° C for 2
Reacted for hours. Then, washing with 100 ml of n-heptane was repeated, and when the chlorine was not detected in the washing solution, the washing was considered to be completed and the catalyst component was obtained. In addition,
At this time, when the solid-liquid in the catalyst component was separated and the titanium content in the solid was measured, it was 2.28% by weight.

〔polymerization〕

700 ml of n-heptane was charged into an autoclave with an internal volume of 2.0, which was completely replaced with nitrogen gas, and 300 mg of triethylaluminum was added while maintaining a nitrogen gas atmosphere.
62.7 mg of phenyltriethoxysilane and 0.62 mg of the above catalyst component as titanium atoms were charged. Then hydrogen gas 16
0 ml was charged, the temperature was raised to 70 ° C., propylene gas was introduced, and the pressure of 6 kg / cm ² · G was maintained to carry out polymerization for 2 hours.

After the completion of the polymerization, the solid polymer obtained was separated, heated to 80 ° C. and dried under reduced pressure to obtain 256 g of a polymer. On the other hand, the liquid was condensed to obtain 2.9 g of a polymer. The MI of the solid polymer is 5.8.
It was.

Example 2 When an experiment was conducted in the same manner as in Example 1 except that the polymerization time was 3 hours, 351 g of a solid polymer was obtained. The MI of the solid polymer was 6.2, and the polymer obtained by condensing the liquid was 4.8 g.

Example 3 Dibutyl phthalate 10.2 instead of dipropyl phthalate
An experiment was conducted in the same manner as in Example 1 using ml. The titanium content in the solid component at this time was 2.57% by weight. The solid polymer obtained after completion of the polymerization was 261 g, and the solid polymer obtained by condensing the liquid was 3.1 g.

The MI of the solid polymer was 6.2.

Example 4 An experiment was performed in the same manner as in Example 1 except that the reaction temperature with TiCl ₄ was 100 ° C. The titanium content in the solid content at this time was 2.69% by weight.

An experiment was conducted in the same manner as in Example 1 except that 52.5 mg of phenyltriethoxysilane was used in the polymerization. The obtained solid polymer was 270 g, and the polymer obtained by condensing the liquid was 3.8 g. The MI of the solid polymer was 4.7.

Example 5 An experiment was conducted in the same manner as in Example 1 except that pulverization was performed at 0 ° C. for 30 hours. The titanium content in the solid content at this time was 2.36% by weight.

After the completion of the polymerization, the amount of the obtained solid polymer was 268 g, and the amount of the polymer obtained by condensing the liquid was 3.7 g. The MI of the solid polymer was 6.1.

[Brief description of drawings]

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

Claims (1)

[Claims] 1. A magnesium compound represented by the general formula MgX ₂ (where X is a halogen element), and (b)
A solid composition obtained by crushing two kinds of electron-donating substances selected from aromatic carboxylic acid esters and silicon compounds each having a Si—O bond at a low temperature of 5 ° C. or lower,
(C) A catalyst component for polymerization of olefins, which comprises contacting a titanium halide represented by the general formula TiX ₄ (where X is a halogen element) and then contacting the titanium halide. Production method.