JPS60149606A - Polymerization of alpha-olefin - Google Patents

Abstract

PURPOSE:To obtain a highly stereoregular poly-alpha-olefin in high yields per unit weight of an active titanium component, by polymerizing an alpha-olefin in the presence of a catalyst comprising an active titanium component, an organoaluminum compound and a specified aromatic carboxylic acid ester. CONSTITUTION:An alpha-olefin is polymerized in the presence of a catalyst comprising an active titanium component obtained by impregnating a magnesium halide with a titanium halide, an organoaluminum compound and an aromatic carboxylic acid ester of an acid value <=0.05mgKOH/g. In order to improve the performance of the active titanium component, it is desirable that the halogen atom in the compounds is chlorine. As the aromatic carboxylic acid ester, an alkyl ester of an aromatic monocarboxylic acid can be desirably used. When the acid value of the ester is larger than 0.05mgKOH/g, the activity at the same addition ratio is poor. When the compounds are added so that the same activity may be obtained, the stereoregularity of the obtained poly-alpha-olefin is lowered.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for polymerizing alpha-olefins. Specifically, the present invention relates to a method for polymerizing α-olefins using a specific catalyst system.

Polymerization of α-olefin using a catalyst consisting of an active titanium component supported on a carrier such as magnesium halide/f: an organic aluminum and an organic acid ester during the polymerization. - Method for improving the stereoregularity of α-olefins
12105, many improved methods have been known, and improvements have been made in the production method of active titanium components. The yield has been significantly improved.

However, in the polymerization of α-olefins such as propylene, it is required to maintain high stereoregularity of the resulting polyα-olefin, so stereoregularity improvers are added, among which aromatic carboxylic acids Esters are known to be effective. However, polyα- obtained by adding aromatic carboxylic acid ester
Although the stereoregularity of the olefin is improved, the yield of polyα-olefin per active titanium catalyst is significantly lowered, so the polyα-olefin that can be obtained while minimizing the decrease in activity.
It is expected that the olefin has high stereoregularity.

As a result of intensive study on the above-mentioned projection, the present inventors discovered that the above-mentioned problems could be solved by using an aromatic carboxylic acid ester that satisfies specific conditions, and completed the present invention.

The object of the present invention is to obtain a stereoscopic configuration of the poly-α-olefin,
It is an object of the present invention to provide a method for polymerizing α-olefins which has high yield properties per active titanium catalyst.

The present invention uses α-
In the method of polymerizing olefins, the acid value is 0.05 m
The present invention relates to a method for polymerizing α-olefins, characterized in that 9KOH/' is used as the following aromatic carbo/acid ester.

In the present invention, known active titanium components obtained by supporting titanium no-rogenide on magnesium no-rogenide can be used, and those obtained by various methods can be used. For example, a method of contacting a liquid mixture containing halogenated titanium or halogenated titanium. A method of co-pulverizing magnesium halide, titanium halide, or magnesium halide, titanium halide, and an organic compound.

A method in which a liquid magnesium compound is treated with a halogen-containing compound to obtain a carrier mainly composed of magnesium halide, and then treated with titanium halide, in which the C-0 bond is removed before or during the treatment with titanium halide. There are methods of making the contained compounds exist.

The halogen atom of the compound used above is preferably chlorine in order to improve the performance of the active titanium component, that is, the magnesium halide is magnesium chloride, and the titanium halide is titanium trichloride or titanium tetrachloride. Titanium chloride, especially titanium tetrachloride, is preferred.

Examples of organoaluminum compounds include trialkylaluminum such as triethylaluminum, tripropylaluminum, tributylaluminum, trihexylaluminum, dialkylaluminum chloride such as diethylaluminum chloride, dipropylaluminum chloride, dibutylaluminum chloride, diakylaluminum chloride, and the above. Dialkyl aluminum bromide or dialkyl aluminum iodide substituted with chloride cafromide can be used alone or as a mixture.

As the aromatic carboxylic acid ester used as the stereoregularity improver in the present invention, alkyl esters of aromatic monocarphonic acids are preferably used, and specifically, methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, toluyl Although notyl acid, ethyl toluate, furovir toluate, butyl toluate, methyl ethylbenzoate, ethyl ethyl benzoate, globinoethyl benzoate, butyl ethyl benzoate, etc. are used, the above-mentioned aromatic carboxylic acid esters are important in the present invention. The acid value measured by a conventional method is o, os m9KOH/f or less. Acid value ≠; 0.05 m9'KOH
When /S' is larger, the activity will be poor at the same addition amount ratio, and when added so as to give the same activity, the stereoregularity of the poly α-olefin obtained will be low. The lower the acid value, the better, but usually o, olrngKOH
/ ft is sufficient.

In the present invention, examples of the α-olefin include propylene, butene-1, hexene-1, etc., which are used for homopolymerization, copolymerization, and copolymerization with ethyray.

The polymerization conditions are the usual conditions, the polymerization temperature is room temperature to 100°C, and the pressure is normal pressure to 5o kg.
/ art-gauge, in the presence of an inert medium such as propane, butane, pentane, hexane, heptane, etc., or a bulk polymerization method using α-olefin itself as a medium, or a gas phase substantially free of liquid medium. It can be polymerized by polymerization method.

By carrying out the method of the present invention, highly stereoregular polyα-olefins can be obtained in high yield based on the active titanium component, which is of industrial value.

The present invention will be explained in more detail with reference to Examples below.

Example 1 A) Production of active Arashi titanium component 20 g of magnesium chloride, 3 ml of tetraethoxysilane
, 4ml of 112-dichloroethane.

The mixture was ground for 40 hours in a grinder containing 80 stainless steel balls with a diameter of 12 mm. 10 g of the obtained co-pulverized product,
Titanium tetrachloride (50 rIL) was placed in a 2001 n, l round bottom flask and treated at 80°C for 2 hours with stirring.Then, the solid part was separated by static separation.
After washing with -hexane five times, it was further treated with 50+ig of titanium tetrachloride at 80°C for 2 hours, and the solid portion was similarly washed eight times with 1]-hexane to obtain an active titanium component slurry.

One part of the slurry was taken out and analyzed for titanium, which was found to contain 2.5 wt% titanium.

B) Polymerization Prepare an autoclave with an internal volume of 5 tons that has been thoroughly dried and purged with nitrogen. On the other hand, 50 m/! in a flask under a 100 me nitrogen atmosphere! +1-hebutane, diethylaluminum chloride I], 128 mg, acid value 0.015'm9
KOH/g of methyl p-toluate (0.06i, triethylaluminum 0081πd1) 20m9 of the above active titanium component was added and mixed, then charged into the above autoclave, and then 1.5Kg of liquid propylene, hydrogen I, 1N4 were added and heated at 75°C for 2 hours. After polymerization, unreacted propylene was purged and white polypropylene powder was taken out at 80°C.
Dry at 60@mHf for 10 hours, weigh, and determine the intrinsic viscosity (1
Measured with a tetralin solution at 65°C, hereinafter abbreviated as η), boiling n
- Hebutane extraction residual rate (after 6 hours of extraction with boiling Rohepkun using a Soxhlet extractor) - Weight x 1oo (
q6) Powder weight before extraction i (hereinafter abbreviated as II) and bulk specific gravity were measured. The results are shown in the table.

Examples 2 to 4 Comparative Examples 1 to 5 Using the active titanium component "2" obtained in A) of Example 1, polymerization was carried out in the same manner as in Example 1 using an aromatic carboxylic acid ester having the acid value shown in the table. Shown in the table.

Claims (1)

[Claims] A method of polymerizing α-olefin using an active titanium component obtained by supporting titanium halide on magnesium halide, an organoaluminum compound, and an aromatic carboxylic acid ester, with an acid value of 0.05 m9
A method for polymerizing α-olefins, characterized by using an aromatic carboxylic acid ester having a KOH/y or less.