JPH07661B2 - Catalyst for olefin polymerization - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention provides a stereoregular polymer having a highly active activity and an ordered particle size distribution in an extremely high yield when subjected to the polymerization of olefins. The present invention relates to a high-performance catalyst component and a catalyst which can be obtained, more specifically, an olefin obtained by bringing a solid composition obtained by bringing a fatty acid magnesium, a diester of an aromatic dicarboxylic acid, and a titanium halide into contact with water. The present invention relates to an olefin polymerization catalyst comprising a catalyst component for polymerization, a silicon compound and an organoaluminum compound.

[Conventional technology]

Conventionally, as a catalyst for olefin polymerization having high activity, a combination of a solid titanium halide as a catalyst component and an organoaluminum compound is well known and widely used. Since the yield of the polymer per titanium (hereinafter referred to as the catalyst component and the polymerization activity per titanium in the catalyst component) was low, a so-called deashing step for removing the catalyst residue was unavoidable. Since this deashing process uses a large amount of alcohol or a chelating agent, a recovering device or a regenerating device for them is indispensable, and there are many resources, energy, and other incidental problems, and those skilled in the art can quickly solve the problem. This is an important issue that is desired. In order to eliminate this complicated deashing step, many studies have been made and proposed to increase the polymerization activity per 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 component 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 dramatically increased. There are many proposals to raise the price.

[Problems to be solved by the invention]

However, the chlorine contained in magnesium chloride, which forms the mainstream as a carrier substance, has the drawback that it adversely affects the polymer produced as well as the halogen element in titanium halides, and therefore the effect of chlorine is virtually ignored. There was an unsolved part such as a high activity required, or the need to keep the concentration of magnesium chloride itself low.

SUMMARY OF THE INVENTION The inventors of the present invention aimed to reduce the residual chlorine in the produced polymer while maintaining the polymerization activity per catalyst component and the yield of the stereoregular polymer at a high level.
In 0454, a method for producing a catalyst component for polymerization of olefins was proposed, and the intended purpose was achieved. Further, when the polymerization of olefins, particularly the stereoregular polymerization of propylene, 1-butene and the like is industrially carried out, it is usually necessary to make an electron donating compound such as an aromatic carboxylic acid ester coexist in the polymerization system. It is indispensable in a catalyst that uses a catalyst component having a carrier of (1) as a carrier in combination with an organic aluminum compound. However, this aromatic carboxylic acid ester imparts an ester odor peculiar to the produced polymer, and its removal is a major problem in the art.

Further, in a so-called highly active supported catalyst, such as a catalyst using a catalyst component having magnesium chloride as a carrier,
Although the activity at the initial stage of the polymerization is high, the deactivation is large, which causes a problem in the process operation, and when it is necessary to prolong the polymerization time such as block copolymerization, it is practically impossible to use. In order to improve this point, for example, in JP-A-54-94590, a catalyst component is prepared by using magnesium dihalide as a starting material, and an organoaluminum compound, an organic carboxylic acid ester, and M-O-R are prepared.
A method of using it for the polymerization of olefins in combination with a compound having a group has been shown, but since the organic carboxylic acid ester is used during the polymerization, the problem of the odor of the produced polymer has not been solved, and As can be seen from the above, very complicated operations are required, and it cannot be said that a practically sufficient one is obtained in terms of performance and sustainability of activity.

Further, although it is necessary to supply the catalyst to a high temperature polymerization tank in an industrial polymerization apparatus, it is known that the performance of the conventional supported catalyst is considerably lowered in such a case. . This is a big problem particularly in the so-called continuous polymerization method, and improvement thereof has been a strong demand in the field.

Also, the particle size distribution of the produced polymer is a very important issue industrially in plant operation, but different processes are required for each process, and it is difficult for conventional supported catalysts to deal with this in detail. It was

The inventors of the present invention have reached the present invention as a result of earnest research in order to solve the problems remaining in such conventional techniques, and make a proactive proposal.

[Means for solving problems]

That is, the features of the present invention are (A) (a) fatty acid magnesium, (b) diester of aromatic dicarboxylic acid, and (c) general formula TiX ₄ (X in the formula:
Is a halogen element. Obtained by contacting (d) water and then (c) the titanium halide to a solid composition obtained by contacting the titanium halide represented by (4) (hereinafter simply referred to as "titanium halide"). (B) General formula SiRm (OR ′) _4−m (wherein R is hydrogen, an alkyl group or an aryl group, R ′ is an alkyl group or an aryl group, and m is 0 ≦ m ≦ No. 4, which is a silicon compound (hereinafter may be simply referred to as a silicon compound); and (C) an organoaluminum compound, which is a catalyst for olefin polymerization.

As the fatty acid magnesium used in the present invention, saturated fatty acid magnesium is preferable, and magnesium stearate, magnesium octanoate, magnesium decanoate and magnesium laurate are particularly preferable.

The aromatic dicarboxylic acid diester used in the present invention is preferably a phthalic acid diester, for example, dimethyl phthalate, diethyl phthalate, dipropyl phthalate, diisopropyl phthalate, dibutyl phthalate, diisobutyl phthalate, diamyl phthalate, diisoamyl phthalate, ethyl. Examples thereof include butyl phthalate, ethyl isobutyl phthalate and ethyl propyl phthalate.

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.

As the silicon compound used in the present invention,
Examples thereof include phenylalkoxysilane and alkylalkoxysilane. Further examples of phenylalkoxysilanes include phenyltrimethoxysilane, phenyltriethoxysilane, phenyltripropoxysilane, phenyltriisopropoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane and the like. Examples of the alkylalkoxysilane include tetramethoxysilane, tetraethoxysilane, trimethoxyethylsilane, trimethoxymethylsilane, triethoxymethylsilane, ethyltriethoxysilane, and ethyltriisopropoxysilane.

When obtaining the solid composition of the present invention, the use ratio of each raw material and the contact conditions are optional, and are not particularly limited, as long as they do not adversely affect the performance of the catalyst component to be produced. 1 g of fatty acid magnesium,
The diester of aromatic dicarboxylic acid is in the range of 0.01 to 2 g, preferably 0.01 to 0.5 g, and the titanium halide is 0.1 g.
The above range is preferably 1 g or more.

Further, the contact of each raw material is usually carried out at a temperature from 0 ° C. to the boiling point of the titanium halide used for 100 hours or less, preferably 10 hours or less.

At this time, the order and method of contacting each raw material are not particularly limited, and any appropriate one can be selected.

The solid 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.

The contact between the solid composition thus obtained and water is usually 1 g of the solid composition, 1 g or less of water is used at 100 ° C. or lower, preferably 50 ° C. or lower for 100 hours or less, preferably Less than 10 hours.

The water used here is preferably used in the form of being contained in an aliphatic or aromatic hydrocarbon or halogenated hydrocarbon.

After the following operation, a titanium halide is further contacted, and washing with an organic solvent such as n-heptane before and after this contact is also one of preferred embodiments.

The catalyst component produced as described above is combined with the silicon compound and the organoaluminum compound to form a catalyst for olefin polymerization. The organoaluminum compound used is 1 in mole ratio per mole of titanium atom in the catalyst component.
Used in the range of up to 1000, and the silicon compound has a molar ratio of 1 or less per mol of the organoaluminum compound, preferably 1 or less.
Used in the range of 0.005-0.5.

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.

Olefins homopolymerized or copolymerized using the catalyst produced by the method of the present invention are ethylene, propylene,
1-butene 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 suppressed to a very low level due to the extremely high activity of the catalyst, and the residual chlorine The effect of chlorine on the produced polymer can be reduced to such an extent that the deashing step is not required at all because of the small amount.

Chlorine contained in the produced polymer causes corrosion of equipment used in processes such as granulation and molding, and also causes deterioration of the produced polymer itself, yellowing, etc. Has a very important meaning to those skilled in the art.

Further, the feature of the present invention is that not only the big problem of the odor of the produced polymer is solved by not using the aromatic carboxylic acid ester during the polymerization, but the activity per unit time of the catalyst is It is an object of the present invention to solve the essential drawback of so-called highly active supported catalysts, which is significantly reduced with the increase of the above, and to provide a catalyst that can be practically applied not only to homopolymerization but also to copolymerization.

Conventionally, in industrial olefin polymer production, it has been generally said that hydrogen is allowed to coexist at the time of polymerization from the viewpoint of MI control and the like. Below, it had the disadvantage that activity and stereoregularity were significantly reduced. However, when olefins are polymerized in the presence of hydrogen using the catalyst obtained according to the present invention, the MI of the produced polymer is
The activity and stereoregularity are hardly deteriorated even when the value is extremely high, and such an effect brings an extremely great benefit to those skilled in the art.

Further, the catalyst component or the catalyst produced according to the present invention has a more ordered particle size distribution, and can exert an industrially extremely beneficial effect that the particle size distribution can be controlled.

〔Example〕

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

Example 1 <Preparation of catalyst component> 200 m fully replaced with nitrogen gas and equipped with a stirrer
10 g of magnesium stearate, 0.6 g of dibutyl phthalate and 25 ml of TiCl ₄ were charged into a 1-liter round bottom flask, and the mixture was reacted at 110 ° C. for 2 hours with stirring. After completion of the reaction, the solid composition was obtained by washing 10 times with 100 ml of n-heptane at 40 ° C. Next, 100 ml of n-heptane containing 10 ppm of water was added to the solid composition, and the mixture was treated at room temperature for 1 hour with stirring.
It was washed 5 times with 100 ml, 25 ml of TiCl ₄ was newly added, and the mixture was reacted at 110 ° C. for 2 hours with stirring.

After the reaction was completed, it was cooled to 40 ° C, and then 100 ml of n-heptane
The washing was repeated, and when chlorine was not detected in the washing liquid, the washing was completed and the catalyst component was obtained. At this time, the titanium content in the catalyst component was measured and found to be 2.41% by weight.

<< Polymerization >> 700 ml of n-heptane was charged into an autoclave equipped with a stirrer and having an internal volume of 2.0 l, which was completely replaced with nitrogen gas, and 301 mg of triethylaluminum, 64 mg of phenyltriethoxysilane, and then the above while maintaining a nitrogen gas atmosphere. The catalyst component was charged with 0.3 mg of titanium atom. Then 120 ml of hydrogen gas
6k while charging propylene gas and raising the temperature to 70 ° C and introducing propylene gas
Polymerization was carried out for 4 hours while maintaining the pressure of g / cm ² · G.
After completion of the polymerization, the solid polymer obtained was separated, 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 liquid is (A), and the amount of the solid polymer is (B). Also, the obtained solid polymer was heated to 6 with boiling n-heptane.
It is extracted with time 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 in the produced polymer is represented by (G) and MI of the produced polymer is represented by (H). The results obtained are as shown in Table 1. As a result of measuring the particle size distribution of the produced polymer, 100 μ or less was 3% by weight.

Example 2 An experiment was conducted in the same manner as in Example 1 except that the polymerization time was 6 hours. The results obtained are as shown in Table 1. The result of particle size distribution measurement of the produced polymer was 100 μm.
The following was 2% by weight.

Example 3 A catalyst component was prepared in the same manner as in Example 1 except that 200 ml of n-heptane containing 10 ppm of water was used. In addition,
At this time, the titanium content in the solid content was 2.52% 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. As a result of measuring the particle size distribution of the produced polymer, 100 μm or less was 2% by weight.

Example 4 An experiment was conducted in the same manner as in Example 1 except that the treatment with n-heptane containing water was conducted at 50 ° C. The titanium content in the solid content at this time was 2.38% 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. As a result of measuring the particle size distribution of the produced polymer, 100 μm or less was 2% by weight.

[Brief description of drawings]

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

Claims (1)

[Claims] 1. A) (a) fatty acid magnesium, (b)
Diesters of aromatic dicarboxylic acids and (c) the general formula Ti
A solid composition obtained by contacting a titanium halide represented by X ₄ (where X is a halogen element) is contacted with (d) water, and then (c) a general formula TiX.
_{4 A} catalyst component obtained by contacting a titanium halide represented by the formula (wherein X is a halogen element); (B) General formula SiRm (OR ') 4-m (wherein R is hydrogen, an alkyl group or An aryl group, R'is an alkyl group or an aryl group, and m is 0≤m≤4); and (C) an olefin polymerization catalyst comprising an organoaluminum compound.