JPS60130606A - Polymerization of olefin - Google Patents

Abstract

PURPOSE:To make it possible to obtain a polyolefin of a low ash content and a good hue, by providing a step of treatment with a magnet after a step of grinding in producing an olefin polymerization solid transition metal catalyst whose production process contains the step of grinding. CONSTITUTION:In producing an olefin polymerization solid transition metal catalyst by using titanium tetrachloride, magnesium chloride, an electron-donating compound, etc., a step of treatment with a magnet is provided after a step of grinding by a grinder. The treatment with a magnet can be performed by, for example, a method in which a ground product is directly contacted with a magnet by placing the latter in the former, one in which the former is treated with the latter during transfer by attaching the latter to a pipe for transfer, and one in which the former is treated with a slurry formed by dispersing the latter in a suitable medium. An alpha-olefin (e.g., propylene) is polymerized in the presence of the obtained catalyst.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for obtaining a polyolefin with relatively little catalyst residue.

Many methods are known for producing catalysts for olefin polymerization, among which are a method in which the catalyst is activated by pulverization, and a method in which a carrier is produced by pulverization and a transition metal is supported on the carrier to produce the catalyst. It is a simple method for producing catalysts and has good reproducibility when carried out on an industrial scale, so it is widely practiced. On the other hand, improvements in catalyst activity have improved the yield of polyolefins, especially those containing solid transition metals, and it has become possible to produce products for general use without substantially removing catalyst residues. However, in special applications such as condenser films, it may be necessary to strictly remove catalyst residues, and even in general applications, this may not be possible due to problems with the weather resistance or color of the polyolefin. It is required that there be as little catalyst residue as possible. Improved catalytic activity eliminates the need for conventional deashing using alcohol or washing with water.By removing catalytic activity with an appropriate catalyst deactivator and then washing with a hydrocarbon solvent, the conventional treatment method can be improved. In some cases, it is possible to reduce the amount of catalyst residue, but in the case of solid transition gold catalysts that include a pulverization process in the catalyst manufacturing process, the color of the resulting polyolefin may be poor, or the amount of catalyst residue may be poor or difficult to use. There was a problem in that only polyolefins containing a much higher total ash content than the total ash content estimated from the metal residue generated from the catalyst produced by the catalyst were obtained.

The inventor of the present invention has conducted intensive studies on methods for solving the above problems, and has found that the above problems can be solved by using a solid transition metal catalyst that has been subjected to a specific treatment during the production process, and has completed the present invention. .

An object of the present invention is to provide a method for producing polyolefin with relatively little catalyst residue.

The present invention relates to a method for polymerizing olefin using a solid transition metal catalyst, which includes a pulverizing step using a pulverizer during the catalyst manufacturing process, in which the olefin is manufactured through a pulverizing step using a pulverizer followed by a catalyst treatment step using a magnet. The present invention relates to an olefin polymerization method characterized by using a solid transition metal catalyst.

In the present invention, the expression "including a pulverizing step using a pulverizer during the catalyst manufacturing process" means that the catalyst will be contained if the pulverizing operation is performed at any stage during the catalyst manufacturing process. T obtained by reducing titanium chloride with aluminum
iC13・'/3 A method of obtaining a solid transition metal catalyst by pulverizing Azcz3, or a method of co-pulverizing it with a suitable organic compound, a suitable support (e.g. silica gel, alumina, manganese halide, halogen A solid transition metal catalyst can be obtained by co-pulverizing a transition metal compound (magnesium chloride, alkoxymagnesium, etc.) and a transition metal compound, or by using a powder obtained by crushing an inorganic compound as a carrier and treating it with a transition metal compound. For example, how to obtain

In the present invention, the phrase "manufactured through a magnet treatment step after the pulverization step" means that a magnet treatment step is provided between the step of polymerizing olefin using a solid transition catalyst and the pulverization step. In other words, there is no pulverization after the magnetic treatment step.

In the present invention, there are no particular restrictions on the method of treating the catalyst using a magnet, and various methods can be employed. For example, a method in which a magnet is inserted into the pulverized material obtained by pulverization and brought into direct contact with the pulverized material, or a magnet is attached to a pipe that transports the pulverized material, and the pulverized material is processed with the magnet while being transported. Examples include a method in which the pulverized material is dispersed in a suitable medium to form a slurry, and then the same operations as above are carried out. In cases where the pulverized material and the magnet are not in direct contact, it is preferable to examine whether the treatment by the magnet is complete by changing the slurry transfer speed, the size of the piping, and the strength of the magnet.

By carrying out the method of the present invention, polyolefins with low ash content and good color can be obtained, which is of industrial value.

The present invention will be specifically explained below with reference to Examples.

Example 1 (i) Preparation of solid transition metal catalyst A vibratory mill equipped with four grinding pots each having an internal volume of 4 tons and containing 9K9 steel balls with a diameter of 12 m was prepared.

600 g of magnesium chloride in a nitrogen atmosphere in each pot;
60 ql of tetraethoxysilane and 45 m6 of α, α, α-trifluorotoluene were added and pulverized for 40 hours.

This operation was repeated to obtain co-pulverized products 6 and 9. Place about 1 garlic clover in a polyethylene bag and place the crushed material under a magnet (product name).
5UNOROWN MAGNETS ITEM A75
M'1no-ru Industries 'ffm
(manufactured by 1ted).

The crushed product 3002 treated with a magnet was placed in a 5 t round bottom flask, 1500 ml of titanium tetrachloride was added, and the mixture was stirred at 80°C for 2 hours, and then the supernatant liquid was removed by decantation.
Next, 4 t of n-heptane was added, stirred for 15 minutes at room temperature, left to stand, and the supernatant liquid removed. After turning the mixture 7 times, an additional 2 t of n-heptane was added to form a solid catalyst slurry. did. When a portion of the solid catalyst slurry was sampled, n-hebutane was evaporated and analyzed, it was found that the solid catalyst contained 15 parts by weight of T1.

Mark) Polymerization Prepare an autoclave with an internal volume of 5 tons that has been thoroughly dried and purged with nitrogen. On the other hand, 100 m4 of n-hebutane, which had been dried and replaced with nitrogen, was placed in a 200 g flask. /ethylaluminum chloride 0.138 mg, p-methyl toluate o, o5mA',) ethylaluminum 0.08
After adding 50 m9 of the above solid transition metal catalyst and stirring, the mixture was charged into the autoclave. Then propylene 1. El K', g, 2.2Nt hydrogen added at 75℃
After polymerizing for 2 hours at
After repeating the operation of charging s Ky and stirring at 60°C for 10 minutes and extracting the supernatant propylene 6 times, the polymer was taken out, dried, and weighed, and the result was 630fi' (% omitted)
It was 978%. Further, the intrinsic viscosity number was measured using a tetralin solution at 165° C. (hereinafter abbreviated as η), and η was 17. Also, the total ash content (combustion residue) is 15
The ppm ash composition is 8ppm for Mpo and 7 for A12o3.
It was ppm. In addition, the hue of the powder was visually determined.

Comparative Example 1 The same procedure as in Example 1 was performed except that the contact treatment with titanium tetrachloride was performed without performing the treatment with a magnet. The results are shown in the table. Total ash content is 20 ppm. Ash composition is MyO: 8 ppm.
At2O3 was 6 ppm.

Example 2 The solid transition metal catalyst slurry obtained in Comparative Example 1 was transferred to another flask through a Teflon tube with an inner diameter of 8 mm. However, at this time, the magnet used in Example 1 was attached to the Teflon tube, and the liquid transfer rate was set to 120 me/sec. Polymerization was carried out in the same manner as in Example 1 using the solid transition metal catalyst slurry thus obtained. The results are shown in the table.

Claims (1)

[Claims] In a method for polymerizing olefins using a solid transition metal catalyst, which includes a pulverization step using a pulverizer during the catalyst production process, the solid transition metal catalyst manufactured through a pulverization step using a pulverizer followed by a catalyst treatment step using a magnet is used. A method for polymerizing olefins, characterized in that it is used.