JPH0710884B2 - Olefin polymerization catalyst - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] A high-performance catalyst which, when subjected to the polymerization of the olefins of the present invention, acts with high activity and is capable of obtaining a stereoregular polymer in an extremely high yield. More particularly, it relates to a catalyst component for olefin polymerization which is obtained by contacting fatty acid calcium, fatty acid magnesium, diester of aromatic dicarboxylic acid and titanium halide, and a catalyst for olefin polymerization comprising a silicon compound and an organic aluminum compound. Is.

[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. The so-called deashing process for removing the catalyst residue was unavoidable because the polymer yield per titanium (hereinafter referred to as the catalyst component and the polymerization activity per titanium in the catalyst component) was low. 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 trend, 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 dramatically increased. There are many proposals to raise the price.

[Problems to be solved by the invention]

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

The present inventors have aimed to reduce 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 107, a method for producing a catalyst component for polymerization of olefins was proposed, and the initial purpose was achieved.

However, in the case of using the above-mentioned catalyst component having magnesium chloride as a carrier, or the catalyst component obtained in the above-mentioned JP-A-59-91107, the polymerization activity per unit time is high at the beginning of the polymerization, but decreases with the passage of the polymerization time. It is large and becomes a problem in process operation, and when it is necessary to prolong the polymerization time such as block copolymerization, it is practically impossible to use.

The present inventors have achieved the present invention as a result of earnest research in order to solve the problems left over in the prior art and to further improve the quality of the polymer produced.

[Means for solving problems]

That is, the features of the present invention are: (A) (a) fatty acid calcium, (b) fatty acid magnesium, (c) diester of aromatic dicarboxylic acid, and (d) general formula TiX ₄ (where X is a halogen element). Is. (B) A catalyst component obtained by contacting a titanium halide represented by (4) (hereinafter, may be simply referred to as “titanium halide”) with a composition obtained by contacting the titanium halide with the composition; It is represented by the 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). Another object is to provide a catalyst for olefin polymerization, which comprises a silicon compound (hereinafter sometimes simply referred to as a silicon compound); and (C) an organoaluminum compound.

As the fatty acid calcium used in the present invention,
Saturated fatty acid calcium is preferred.

As the fatty acid magnesium used in the present invention, saturated fatty acid magnesium is preferable.

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

Examples of the titanium halide represented by the general formula TiX ₄ (wherein 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.

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.

Examples of the organoaluminum compound used in the present invention include trialkylaluminums, dialkylaluminum halides, alkylaluminum dihalides, and mixtures thereof.

When obtaining the catalyst component in the present invention, the use ratio of each raw material, the contact conditions, and the like are arbitrary and are not particularly limited as long as they do not adversely affect the performance of the catalyst component to be produced, but usually fatty acids The diester of aromatic dicarboxylic acid is in the range of 0.01 to 2 g, preferably 0.1 to 1 g, and the titanium halide is in the range of 0.1 g or more, preferably 1 g or more based on 1 g of calcium and fatty acid magnesium in total.

At this time, the order of contact and the method of contact of the respective raw materials forming the catalyst component are not particularly limited and can be arbitrarily selected.

It is necessary to further contact a titanium halide with the composition obtained after contacting each component constituting the catalyst component, and it is also possible to wash with a 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 has broad peaks near 2θ = 32 ° and around 50 ° in its X-ray spectrum, and is used in combination with the above-mentioned silicon compound and organoaluminum compound to form a catalyst for olefin polymerization. Form. The organoaluminum compound used is used in a range of 1 to 1000 in molar ratio per mole of titanium atom in the catalyst component, and the silicon compound is 1 or less in molar ratio per mole of organoaluminum compound, preferably 0.005 to 0.5. Used in the range of.

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 component of the present invention are ethylene, propylene, 1-butene and the like.

〔The invention's effect〕

When olefins are polymerized by using the catalyst component and the catalyst obtained according to the present invention, the produced polymer has extremely high stereoregularity and, of course, has a very high activity and thus the produced polymer. The catalyst residue in the inside can be kept extremely low, and the amount of residual chlorine is so negligible that no deashing step is required at all, and of course the effect of chlorine on the produced polymer is substantially eliminated. Can be extinguished.

Chlorine contained in the generated polymer causes corrosion of equipment used in processes such as granulation and molding, and also causes deterioration of the generated polymer itself, yellowing, etc., which can be substantially eliminated. This is extremely important to those skilled in the art.

As can be seen from the fact that fatty acid calcium is generally used as a stabilizer for polymers in the present invention, even if it remains in the polymer obtained by using the catalyst component of the present invention, it does not adversely affect the polymer. Is not considered at all, and on the contrary, it is expected to contribute to the stability of the polymer.

Further, a feature of the present invention is that the activity of the catalyst component per unit time is significantly reduced with the progress of polymerization,
It is an object of the present invention to solve the essential drawbacks of so-called highly active supported catalysts and to provide a catalyst that can be practically applied not only to homopolymerization but also to copolymerization.

Further, in industrial production of olefin polymers, coexistence of hydrogen at the time of polymerization is generally considered from the viewpoint of MI control and the like, but the catalyst component using magnesium chloride as a carrier is active in the presence of hydrogen. And the stereoregularity is significantly reduced. However, when the olefins are polymerized in the presence of hydrogen using the catalyst component and the catalyst obtained according to the present invention, almost no activity and stereoregularity are obtained even when the MI of the produced polymer is extremely high. Does not decrease, and such an effect brings an extremely great benefit to those skilled in the art.

〔Example〕

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

Example 1 [Preparation of catalyst component] 2.0 g of calcium stearate and 8.0 g of magnesium stearate were placed in a round bottom flask having a capacity of 300 ml, which was sufficiently replaced with nitrogen gas and equipped with a stirrer, and 1.5 ml of dibutyl phthalate and Add TiCl ₄ 100ml, 110 ℃
The temperature was raised to 2, and the reaction was carried out while stirring for 2 hours. After the reaction
After washing 10 times with 100 ml of n-heptane at 40 ° C, fresh TiCl ₄ 1
00 ml was added and 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 cleaning was repeated, and when chlorine was not detected in the cleaning liquid, the cleaning was completed and the catalyst component was used. At this time, the solid content of the catalyst component was separated, and the titanium content in the solid content was measured and found to be 2.39% by weight.

[Overlap]

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 301 mg of triethylaluminum was added while maintaining a nitrogen gas atmosphere.
64 mg of phenyltriethoxysilane and then 0.3 mg of the above catalyst component as titanium atoms were charged. Then hydrogen gas 120
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 the completion of the polymerization, the solid polymer obtained was separated, heated to 80 ° C. and dried under reduced pressure to obtain 262 g of a polymer. Meanwhile, the liquid was condensed to obtain 5.1 g of a polymer. The MI of the solid polymer is 6.8.
It was.

Example 2 An experiment was conducted in the same manner as in Example 1 except that the polymerization time was 6 hours, and 360 g of a solid polymer was obtained. Meanwhile, the liquid was condensed to obtain 6.9 g of a polymer. The MI of the solid polymer was 4.8.

Example 3 A catalyst component was prepared in the same manner as in Example 1 except that the reaction temperature was 100 ° C. 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 to obtain 276 g of a solid polymer. Meanwhile, the liquid was condensed to obtain 6.2 g of a polymer. The solid polymer MI was 7.8.

[Brief description of drawings]

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

Claims (1)

[Claims] 1. A compound represented by (A) (a) fatty acid calcium, (b) fatty acid magnesium, (c) diester of aromatic dicarboxylic acid and (d) general formula TiX ₄ (wherein X is a halogen element). to set an organism obtained by contacting a titanium halide, a catalyst component obtained by further contacting the titanium halide, (B) the 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 organoaluminum compound, which is a polymerization of olefins. Catalyst.