JPS6036509A - Polymerization of ethylene - Google Patents

Abstract

PURPOSE:The polymerization of ethylene is carried out in the presence of a catalyst composed of a specific solid component and an organoaluminum compound in a tubular type reactor at high temperature and high pressure to achieve the high-yield polymerization of ethylene per the amount of the catalyst. CONSTITUTION:The polymerization of ethylene or a mixture thereof with an alpha- olefin of 3 or more carbon atoms is carried out in a tubular type reactor at a temperature higher than 125 deg.C under a pressure of higher than 200kg/cm<2> in the presence of a catalyst composed of A and B components which will be stated later. (A) the solid component is prepared by dissolving magnesium halide in an alcohol of ROH (R is 1-8C alkyl), activating the magnesium compound by distilling off the alcohol, then crushing it together with an aluminum halide, treating them with an ether of R-O-R, and bringing the product into contact with a titanium compound of (RO)lTiX4-l (X is halogen; 0<l<4), then finally allowing the product to react with RmAlX3-m (m=1-2). (B) component is an organoaluminum compound of RnAlX3-n (n is 1-3).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the high temperature, high pressure polymerization of ethylene using a tubular reactor.

A method is known in which ethylene is polymerized in the presence of a Ziegler type catalyst at a temperature of 125° C. or higher and a pressure of 200 kg/c1/1 or higher. As for the above catalyst.

Titanium component 2 For example, a combination of titanium trichloride, a titanium compound supported on a magnesium compound, and an organic aluminum compound has been proposed (for example, 1%
No. 97087, No. 56-18607, No. 57-190
No. 009).

The high temperature, high pressure polymerization of ethylene is carried out using a tube reactor or a seed reactor. Because the monomer residence time in a tubular reactor is extremely short compared to that in a seed reactor, the catalyst used for ethylene polymerization in a tubular reactor has a quick start-up for the single polymerization reaction and a high activity. It must be. All of the proposed catalysts have a slow reaction start-up, so if they are applied to ethylene polymerization in a tubular reactor, the productivity of polyethylene will be low, and the peak of exothermic heat due to the polymerization reaction will occur at the outlet of the reactor. The operations after the 1st polymerization reaction become difficult.

The present invention provides a process for polymerizing ethylene that is free from these drawbacks.

The present invention provides ethylene or ethylene and α-
The mixture with olefin is prepared by adding the following component [A] and component [B].
] in a tubular reactor in the presence of a catalyst obtained from
This is an ethylene polymerization method characterized by polymerization at a temperature of .degree. C. or higher and a pressure of 200 Kq/aA or higher.

Component CA] (1) After dissolving magnesium halide in an alcohol represented by the formula ROH, the alcohol is distilled off to prepare activated magnesium halide. Co-milled with aluminum halide.

(3) Treating the co-pulverized product with an ether represented by the formula R-0-R.

(4) contacting the treated solid with a titanium compound represented by the formula (RO)zTiX4-z;

(5) A solid catalyst component obtained by reacting a contact solid with an organoaluminum ride represented by the formula R1nA/LX3-m.

Component [B] An organic aluminum compound represented by the formula RnA4X3-n.

(In each of the above formulas, R represents an alkyl group having 1 to 8 carbon atoms, X represents a halogen atom, t is a number greater than or equal to 0 and less than 4, 1m is a number greater than 1 and less than or equal to 2, and n is 1
The number is greater or less. ) The catalyst used in the present invention allows the polymerization reaction to take place quickly and is highly active, giving polyethylene in a high yield per catalyst used.

The solid catalyst components of the present invention are prepared using substantially anhydrous compounds under an inert gas atmosphere such as nitrogen, aviregon, etc.

Specific examples of magnesium halides include magnesium chloride, magnesium bromide, and red sea bream sium iodide.

Specific examples of alcohols include methanol, ethanol, propatool, butanol, hexanol, and octatool. The amount of alcohol to be used is sufficient as long as it is sufficient to dissolve the halogenated red sea bream sium, and is usually 6 moles or more per 1 mol of red sea bream sium halogenide.

+, , L After dissolving red sea bream sium halide in alcohol, the alcohol is distilled off to obtain activated magnesium halide. It is desirable that this activated red sea bream sium halide is dried before being subjected to co-pulverization with aluminum halide.

Specific examples of aluminum halides include aluminum chloride, aluminum bromide, and aluminum iodide. The amount of aluminum halide used is preferably 0.05 to 5 parts by weight and 1% to 1 to 2 parts by weight per 1 part by weight of activated magnesium halide.

Co-milling can be carried out using known mills 9, such as ball mills, vibrating ball mills, informal mills, and jet mills. Co-grinding time is usually 1 to 100 hours.

A specific example of ether is ethyl ether.

Examples include phthyl ether and amyl ether. The amount of ether used is preferably 0.1 to 100 mol, particularly 0.5 to 50 mol, per mol of aluminum halide in the co-pulverized product.

Ether treatment generally involves suspending the co-pulverized material in ether or a mixed solution of ether and an inert hydrocarbon solvent, and
This is carried out by stirring for 05-10 hours at a temperature of 0-100°C. After the ether treatment, the treated solids are separated,
Wash with inert hydrocarbon solvent.

Specific examples of titanium compounds include methoxytitanium trichloride, quintitanium trichloride, butoki/
Titanium trichloride, octoxotitanium trichloridemide, etquin titanium triiodite, /ethgia titanium dichloride, zigutoquin titanium dichloride, dihexoxytitanium dichloride, triethoxotitane chloride, tributoxytitanium chloride, trihexoxytitanium chloride .

Examples include titanium tetrabromide and titanium tetrabromide.

There is no particular restriction on the amount of the titanium compound used, but it is generally 10 to 1000 mmol per 11 solids to be treated.

The contact temperature is usually from 20 DEG C. to the boiling point of the titanium compound, and the contact time is usually 0.5 to 10 hours. After the contact treatment, the contact solids are separated (~, washed with an inert hydrocarbon solvent).

As a specific example of aluminum cordless handset/ride.

Diethylaluminum chloride, /ethy/l aluminum bromide, diethylaluminium-L-mini V-iodite, dibutylaluminum chloride, /hexylaluminum chloride, nitylaluminum sesquichloride. and butinoshi aluminum; and 11 sesquichloride.

The amount of organoaluminum light used is 0.1 to 100 mol, especially 0.1 to 100 mol, per gram atom of titanium in the contact solid.
．． Preferably it is 5 to 50 moles. .

What is the reaction between the contact solid and organic aluminum rhamnolide? Generally, 1 tC is carried out by suspending the contact solid in an inert hydrocarbon solvent and adding to this suspension an inert hydrocarbon solution of an organoaluminum uride. The reaction temperature is usually 20 to 100°C, and the reaction temperature is usually 0.5 to 1
It is 0 hours. After the reaction, the obtained solid catalyst component (component [
A]) is separated and washed with an inert hydrocarbon solvent.

Specific examples of inert hydrocarbon solvents used in each step of preparing the solid catalyst component include hexane. Examples include aliphatic hydrocarbons such as hepkune, aromatic hydrocarbons such as l-luene, be/zene, xylene, and halides of these hydrocarbons. .

Specific examples of organoaluminum compounds (component [B]) include tributyl aluminum, tributyl aluminum, trihexyl aluminum, trioctyl aluminum, diethylaluminium chloride, dibutyl aluminum chloride, diethylaluminum bromide, diethylaluminium bromide, diethylaluminium. Iodite, ethylaluminum sesquichloride.

and U-butylaluminum sesquichloride.

The amount of organoaluminum compound used is usually 1 to 1000 moles per gram atom of titanium in component CAI.

In the present invention, an ethylene homopolymer or an ethylene gopolymer is obtained by polymerizing ethylene or a mixture of ethylene and an α-olefin having at least the number of carbon atoms in the presence of a catalyst obtained from component [A] and component CDI. .

As a specific example of an α-olefin with a carbon number of -L (d,
7' Robylene, butene-1,4-methylpentene-1
, octene-1.

The polymerization pressure is 200 Kg 10r/1 or more, 500-3000 Kg/aA. Polymerization temperature is 125°C or higher, preferably 150-350°C
It is ℃. The average residence time of the monomer within the polymerization system is 2~
120 seconds.

Preferably it is 10 to 60 seconds.

A front type reactor is used as the polymerization apparatus.

The molecular weight of the polyethylene produced can be easily controlled by adding a molecular weight regulator, such as hydrogen, to the yarn.

Next, examples will be shown. In the following, "polymerization activity" means M
Component [A]i! subjected to the synthesis reaction The yield of poly titanium (7) is
Melt index of polyethylene measured at 190° C. under a load of 2.16 Ky according to 2003-238. In an example,
All solid catalyst components were prepared in a dry nitrogen gas atmosphere.

Example 1 (1) Preparation of solid catalyst component 105 mol of anhydrous magnesium chloride was mixed with 100 mol of ethanol.
4 and then ethanol was distilled off. The precipitated crystals were dried at 200°C for 10 hours.

15 moles of the obtained activated magnesium chloride and aluminum chloride were placed in a vibrating ball mill and co-milled at room temperature for 5 hours.

Co-pulverized product 5K, 9 was suspended in 100 t of n-hebutane with 7.5 mol of diisoamyl ether,
! 11'+, ii stirred. At the same temperature, the treated solids were separated and washed with +n-hebutane.

The treated solid was suspended in n-hebutane bat, and 182 mol of titanium tetrachloride was added thereto.

The mixture was stirred at 90°C for a period of time. The contact solids are separated from each other at the same temperature,
Washed with n-hebutane.

The contact solid was suspended in n-heptane 607, and 20 t of D-hebutane containing 40 mol of diethylaluminium chloride was added thereto, and the mixture was reacted at 90°C for 6 hours. The obtained solid catalyst component was separated at 90° C. and washed with n-hebutane. The titanium content of the solid catalyst component was 2.0% by weight. Add Shellzuru 71 (manufactured by Shell Chemical) to the solid catalyst component.

15? /L of slurry was prepared.

(2) In a reaction tube with a total polymerization length of about 400 mm, add 60 ethylene polymers h1
Continuously supplying 0.2 volume of hydrogen to the monomer and the monomer consisting of butene-140% by weight,
Ethylene and butene under pressure of 0 Kq/c7/l
1 was copolymerized.

” - solid catalyst component slurry and Scherzl 71 solution of diethylaluminium chloride (concentrated &: 890 mmol/z) at 2.41/hr and 3.427/hr, respectively.
It was continuously fed from an injection point provided at the inlet of one reaction tube at a rate of 1 hour. The temperature inside the reaction tube was set at 145°C at the inlet.
The maximum temperature was kept at 200°C. The flow rate of the monomer in the reaction tube was 1 o 4.7 seconds. The above continuous operation was performed for an hour.

M, 1.5.8 g 710 min, an ethylene/butene-1 copolymer with a density of 0.922 g/- was obtained with a polymerization activity of 22300.

Example 2 Jj2 (Example 1 was repeated except that the amount of aluminum oxide used was changed to 9 moles.

M, engineering, 5.14i', 710 minutes, density 0.923
Y/ar? The ethylene/butene-1 copolymer of r is 1
It was obtained with a polymerization activity of 8,500.

Examples B and 4 Example 1 was repeated, except that 7.5 mol of the ether listed in Table 1 was used instead of the /isoamyl ether. The results are shown in Table 1.

Table 1 Example 5 Example 1 was repeated, except that 180 mol of n-butoxytitanium trichloride was used instead of titanium tetrachloride.

1 letter. 1.5.2 i? /10 min, density 0.921 y
10A ethylene/butene-1 copolymer is 2240
It was obtained with a polymerization activity of 0.

Patent applicant Ube Industries Co., Ltd.

Claims (1)

[Claims] Ethylene or a mixture of ethylene and an α-olefin having 6 or more carbon atoms is heated at 125°C in a tubular reactor in the presence of a catalyst obtained from the following components [A] and [B]. A method for polymerizing ethylene, characterized in that the polymerization is carried out at a temperature of at least 20 oKg/, and at a pressure of at least 20 oKg/ii. Component [A] (1) After dissolving magnesium halide in an alcohol represented by the formula ROH, the alcohol is distilled off to prepare activated magnesium halide. (2) Activated magnesium halide is dissolved in aluminum Co-pulverized with halide. (3) Treating the co-pulverized product with an ether represented by the formula R-0-R. (4) Contacting the treated solid with a titanium compound represented by the formula (RO)zTiX4-z. (5) A solid catalyst component obtained by reacting a contact solid with an organoaluminum halide represented by the formula RmAI X3-m. Component [B] An organoaluminum compound represented by the formula RnaX 3- n . (In each of the above formulas, R represents an argyl group having 1 to 8 carbon atoms or a halogen atom, t is a number greater than or equal to 0 and less than 4, and 1m is a number greater than 1 and less than or equal to 2); n is a number greater than 1 and less than or equal to b. )