JPS6011044B2 - How to polymerize ethylene - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for polymerizing ethylene using a novel catalyst.

More specifically, the present invention relates to a method for producing polyethylene that has a narrow molecular weight distribution and excellent moldability by polymerizing ethylene by solution polymerization using a novel catalyst containing titanium and vanadium.

Solution polymerization is already known as a suitable method for producing 4-polyethylene. The advantages of this solution polymerization include the following. Ethylene polymerization is an exothermic process, and heat generation is a major problem in the process.

Since the reaction temperature of solution polymerization is high, there can be a large temperature difference between the internal temperature and the jacket, resulting in good heat removal efficiency. In terms of temperature control, the higher the temperature, the better. (2) The degree of polymerization of ethylene, that is, the molecular weight of polyethylene, can be controlled relatively accurately by changing the reaction temperature, and molecular weight control can be achieved by using a small amount of hydrogen. There is a correlation between the molecular weight of the polyethylene glue and the viscosity of the reaction solution, so by measuring the viscosity of the solution inside the reactor, the molecular weight of the polyethylene can be estimated and prompt action can be taken.

'4) Polyethylene is generally used in the form of pellets, and polyethylene produced by suspension polymerization or gas phase polymerization is in the form of powder, and extra energy is required to form it into pellets using an extruder.

In solution polymerization, the solvent can be evaporated and distilled off using polymerization heat, and molten polyethylene can be introduced into the extruder, so energy can be used effectively. To take advantage of this advantage, it is desirable that the polymerization temperature be higher. On the other hand, a problem with solution polymerization is that increasing the solution concentration or increasing the molecular weight of polyethylene increases the solution viscosity and reduces production efficiency.

To solve this problem, it is necessary to raise the polymerization temperature and lower the solution viscosity. However, when the polymerization temperature is raised, the catalyst efficiency decreases and a large amount of catalyst residue remains in the polyethylene. This results in coloring of the polyethylene and deterioration of the product after molding. Furthermore, it is difficult to remove the catalyst remaining grooves. Therefore, there is a need for a catalyst that has high catalytic efficiency at high temperatures so that there is little catalyst residue in polyethylene and no removal step is required. In the suspension polymerization method,
Many Ziegler-type catalysts with high catalytic efficiency are known.

However, the catalyst efficiency of these catalysts generally decreases as the polymerization temperature is raised, and the decrease is particularly significant at temperatures above 150° C., and the performance is insufficient for eliminating the catalyst residue removal step in solution polymerization. Recently, a solution polymerization catalyst for Q-olefin using an organoaluminum, an organomagnesium, a titanium compound, and a vanadium compound has been disclosed (Tsubaki Kaisho 53-13
4 total 9).

This catalyst has higher catalytic efficiency compared to conventional catalysts, but
This is not sufficient to omit the catalyst residue removal step. Moreover, this catalyst cannot be stored after mixing the various catalyst components because the catalyst efficiency decreases due to aging of the catalyst and the molecular weight distribution of the produced polyethylene changes. Moreover, performance deteriorates unless sufficient mixing is carried out before introduction into the polymerization system, making it difficult to continue a stable polymerization reaction. As a result of studying solution polymerization catalysts, the present inventors found that they combined an organoaluminum compound with a catalyst component made by contacting a titanium compound and a vanadium compound with a reaction product of a special organomagnesium compound and a specific metal halide. As a result, the catalyst efficiency is extremely high, and temperatures above 150°C, especially at 18°C
The present inventors have discovered a catalyst that exhibits little reduction in catalyst efficiency even at temperatures above 0 and 0, and is stable and can be stored for a long period of time, leading to the present invention.

That is, the present invention provides (i) general formula MQ MgBR with R cost
Metal atom of group m, 8 is a number greater than or equal to 1, Q, p, q, r,
s is 0 or a number greater than 0, p+q+r+s=mQ+2
8, OS (r+s)/(Q+8)≦1, and m
is the valence of M, R1 and R2 are hydrocarbon groups having 1 to 20 carbon atoms which may be the same or different, X1 and X2 are the same or different groups and are hydrogen atoms, OR3,06, R4R5R6,
Represents the group NR7R8, SR9, R3, R7, R8
, R9 is a hydrocarbon group having 1 to 20 carbon atoms, R4, R5
, R6 represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms) and [il] boron, silicon, germanium, tin, lead, phosphorus, arsenic, A reactant of one or a mixture of two or more selected from antimony, bismuth, and mercury halides, and (iii) a mixture or reactant of a titanium compound and a vanadium compound number 1 to 1'100. Reaction product [A] formed by contacting
, or a method in which ethylene is polymerized using the reaction product [A] and the organoaluminum compound [B] under one-stage or multi-stage polymerization conditions in the range of 120 to 350°C.

The features of the present invention will be explained below.

The first feature of the present invention is high catalyst efficiency.

As is clear from the examples described later, the catalyst efficiency is 500k.
It is possible to achieve a polymer thickness (Ti+V) of 9 or more, and it is possible to omit the catalyst removal step. on the other hand. The system shown in Comparative Example 1 that does not use metal halide has uneven catalyst efficiency.
The superiority of the present invention is obvious. The second feature of the present invention is that it is stable even at high temperatures. As is clear from the examples below, it is possible to achieve a catalyst efficiency of 500 k9 polymer/unit (Ti 10 V) at temperatures above 180°C. The third feature of the present invention is that the catalyst can be stored for a long period of time.

As in Comparative Examples 1 and 2, in systems that do not use metal halides, the catalytic efficiency decreases to 1/100 after one month, making them almost unusable. However, surprisingly, as shown in Example 17, the catalyst of the present invention showed no decrease in catalyst efficiency even after one month. As stated above,
The catalyst of the present invention has high catalytic efficiency and is stable at high temperatures,
Furthermore, it has excellent long-term storage resistance.

The general formula MQMg8R used in the catalyst of the present invention also has R cost
The organomagnesium compound (i) (where X1, X2, Q, 8, p, q, r, s are as defined above) will now be described.

Although (ii) is shown as a form of organomagnesium compounds, it encompasses all R2Mg and their combinations with other metal compounds. In the above formula, M can be a metal atom belonging to Group 1 to Group M of the periodic table, such as lithium, sodium oxide, potassium, beryllium, calcium, strontium, barium, zinc, boron, aluminum, etc. However, lithium, beryllium, boron, aluminum, and zinc are particularly preferred because they easily form hydrocarbon solvent-soluble organomagnesium rust. More preferably, aluminum is used. The ratio of magnesium to the metal atom surface can be arbitrarily set, including dialkylmagnesium derivatives where Q = 0.
Preferably, an organomagnesium key body soluble in a hydrocarbon solvent with 0<hi≦5o, particularly o-5≦≦・o is preferable.
The hydrocarbon group represented by RI to R9 is an alkyl group, cycloalkyl group, or allyl group having 1 to 2 carbon atoms, such as methyl, ethyl, propyl, butyl, amyl, hexyl, decyl, cyclohexyl, Examples include phenyl and benzyl groups, and particularly R1 and R2 are preferably alkyl groups, and R4, R5, and R6 are hydrogen atoms. On the other hand, when Q=0, in order to obtain a hydrocarbon solvent soluble organomagnesium compound, R1
, R2 are limited. For example, the first one is R
In the second case, I and/or R2 are secondary or tertiary alkyl groups having 3 or more carbon atoms, and RI is an alkyl group having 2 to 6 carbon atoms, and RI is an alkyl group having 4 or more carbon atoms. group, and the difference in the number of carbon atoms between RI and R2 is 2 or more. Specifically, (sec-C4
) 2Mg, (sec-C4 day 9)Mg (n-C4)
, (iso-C 3 days 7) Mg (n-C4 ratio), (C2 ratio) Mg (n-C 4 days 9), etc. are used. Symbol Q, 8,
The relational expression P+q+r+s=mQ+28 among p, q, r, and s indicates the stoichiometry between the valence of the metal atom and the substituent, and is in a preferable range of 0≦(r+s)/(Q18)≦1. 0
indicates that the sum of XI and X2 is 0 or more and 1 or less with respect to the sum of metal atoms.

In order to increase the stability of the catalyst component [A], it is necessary to add XI to the substituent.
Alternatively, it is recommended that X2 be contained, that is, (r+s)>0. These organomagnesium compounds have the general formula R
IMgQ, a compound represented by R Mg (RI has the above meaning and Q is a halogen atom) and a compound represented by the general formula MR
2m, MR also X1bX2c, MQaX1bX2c (M,
R2, X1, X2, Q, m have the above meanings, a, b
, c is a + b + c = m) in an inert hydrocarbon such as hexane, hebutane, octane, cyclohexane, benzene, toluene, etc.
If necessary, the compound can be synthesized by reacting the compound with an alcohol, cycloxane, amine, imine, thiol or dithio compound.

Furthermore, organomagnesium compounds include MgX chamber, RIMg
XI and M old 2'm, MR steep-, day, or RIMgX1
, R Mg and R2mMX deprivation-n, or RIMgX1,
Rashi Mg and
1, X2, m have the above-mentioned meanings, including the case where X1 and X2 are halogens, and d is a number from 0 to m). Generally, organomagnesium compounds are insoluble in inert hydrocarbon solvents, and organomagnesium compounds where Q>0 are soluble.

In the present invention, it is necessary to use a soluble organomagnesium compound. Also, certain organomagnesium compounds, such as (sec-C4day9)2Mg, (
Although q=0, Mg (n-C4) and the like are soluble in hydrocarbon solvents, and such compounds can of course be used in the present invention to give preferable results. Then boron, silicon, germanium, tin, lead, litho, arsenic,
Halides of antimony, bismuth or mercury (ii
) will be explained.

The term "halide" refers to a compound in which at least one halogen atom is directly bonded to the above atom, and preferably boron, silicon, or germanium chloride is used.
Specifically representing these compounds, 8CI3, C2
Day 5BC12, (C2戊)28CI, SIC14
, SIC13, SIC13・C ratio, SIC12・Japan・
CH3, SIC1 (C is) 3・SIC12・(C2 day 5
)2, QC14, Ge(CH3)2CI2, SnC14
, PCl3, SKI5, (C2day5)2SOCI, etc. can be used alone or in the form of a mixture. In order for the reaction to proceed uniformly, it is desirable to be soluble in a hydrocarbon solvent. Particular preference is given to using silicon compounds containing at least one chlorine atom and one hydrogen atom. The titanium compound and vanadium compound (iii) will be explained.

As titanium compounds, TIC14, TIC13 (OC
2 days 5), TIC13 (0i-C3 days 7), TIC13
(om-C4), TIC12 (0i-C3 day 7) 2,
TIC12 (0n-C4 ratio) 2, TIC1 (0i-C3
Day 7) 3, TIC1 (0n-C4 ratio) 3, Ti (0i-
C3 day 7) 4, Tj (0n-C4 day 9) 4, TiBr4
, Ti14, and other halides, alkoxy halides, and alkoxides are used. Vanadium compounds include VC14, VOC13, VOC12 (0n-C4
), VOC1(0n-C4day9)2,V0(0n-C
4 ratio) 3, VC13 (0-C2 &) etc. genide,
Oxyhalides, alkoxyhalides, alkoxyoxyhalides and alkoxides are used. Preferably, a titanium compound and a vanadium compound containing at least one halogen atom are used, and TIC14, VC14 or VOC13 are particularly preferably used. In order to maintain high catalytic efficiency in high-temperature polymerization, it is necessary to use both a titanium compound and a vanadium compound.
Equimolar ratio is preferably 100/1 to 1/100 < is 1/20
-20'1, more preferably in the range of 1'5 - 10/1.

Reactions (i), (ii), and (iiD) are carried out using inert reaction solvents such as aliphatic hydrocarbons such as hexane, hebutane, and octane, aromatic hydrocarbons such as benzene and toluene, and cyclohexane and methylcyclohexane. The reaction can be carried out in an alicyclic hydrocarbon or a mixture thereof. In terms of catalyst performance, an aliphatic hydrocarbon solvent is preferably used. In order for Z to exhibit highly active catalytic performance, it is necessary to avoid contact between (i) and (iii) in advance.
The surprising effects of the present invention can be achieved by producing a solid component through the reaction of ) and (ii), and by effectively bringing (iii) into contact with the surface of this solid component. (i) and (i
The reaction i) can be carried out by a simultaneous addition method in which two components are simultaneously introduced into the reaction zone and reacted, or by a so-called direct addition method in which one component is charged into the reaction zone in advance and the remaining component is introduced and reacted. Any of the (reverse) two-addition methods is possible.

The reaction temperature is not particularly limited, but is preferably 0 in view of reaction progress.
It is carried out between 150:00 and 150:00, particularly preferably between 20 and 10:00. There is no particular restriction on the reaction ratio of the two components, but preferably 0.01 to 210 hol of component (ii) to 1 mol of component (i), particularly preferably 0.1 to 2 mol.
A range of melon hols is recommended.

A solid component is produced by the reaction of (i) and (ii),
This can be used alone in a furnace or after cleaning by decantation, and then subjected to the reaction with oii), but in order to simplify the reaction operation, this It is preferable to introduce (iii) into the reaction solution to further advance the reaction. The amount of Old used is such that the molar ratio is 3≦Mg/(Ti+V)≦500, preferably 10S
It is preferable that Mg/(Ti+V)≦100 be used, and the concentration of Ti+V in the reaction solution be 34 mol/or less. The reaction temperature is not particularly limited, but is preferably carried out within the range of -30 to 15,000 in order to proceed with the reaction. Catalyst component A of the present invention is useful as a catalyst for ethylene polymerization as it is, but it becomes an even more excellent catalyst when combined with an organoaluminum compound.

As organoaluminum compounds, AI (C2 day 5) 3, Yama (C3 day 7) 3, AI (C4 day 9)
3, AI (C phantom,.) 3, AI (C6 day, 3) 3, Mountain (
Trialkyl aluminum such as C8 day, 7) 3, AI (C, oHa) 3, AI (C2 day 5) 2, CI, rainbow (C2
Day 5) Aluminum halides such as CI2, AI (i-C4) 2CI, AI (Cp5) 2Br, N (C2 day 5)
) 2 (OC 2 days 5), AI (i-C 4 days 9) 2 (OC 4
Alkoxy aluminum such as day 9), AI (C2 day 5)
2・(OSiH・C瓜・C2日5), N(i-C4th)
- Siloxyalkylaluminiums such as (OSi(CH3)2.1-C4day9)2, and mixtures thereof are used.

Catalyst components [A] and [B] may be added into the polymerization system under polymerization conditions, or may be roughly combined in advance prior to polymerization.

Furthermore, the ratio of both components to be combined is as follows: Ti in component [A]
and V, M in the [A] component and A in the [B] component
It is defined by the molar ratio of I, preferably (M 10 mountains)/(Ti
+V) is in the range of 3/1 to 1000/1, more preferably in the range of 5/1 to 500/1. The catalyst of the present invention is
Although it is suitable for the polymerization of ethylene, Q-olefins having 3 or more carbon atoms such as propylene, butene-1/isobutene, hexene-1,4-methylbentene-1, octene-1, decene-1, etc. It is also possible to copolymerize with ethylene in the presence of hol% or less, and homopolymerization and copolymerization can achieve a density of 0.975-0.
It is possible to produce polyethylene in the 910 range.

Polymerization is carried out from 120 to 350 pm, preferably from 150 to 320 pm.
It is carried out using a solution polymerization method in a temperature range of 1:00 pm.

As the polymerization solvent, aliphatic hydrocarbons such as hexane, hebutane, and octane, aromatic hydrocarbons such as benzene, toluene, and xylene, and alicyclic hydrocarbons such as cyclohexane and methylcyclohexane are used. The catalyst is introduced into the reactor together with the polymerization catalyst, and ethylene is introduced under an inert atmosphere at a partial pressure of preferably 0.1 to 4 Mpa, more preferably 1 to 28 Mpa, and the ethylene and catalyst are brought into contact with each other. Polymerization can be carried out by means such as mixing in a flywheel so that the polymerization is good. The polymerization may be carried out in a single-stage polymerization using one reaction zone, or it is also possible to carry out a so-called multi-stage polymerization using a plurality of reaction zones.

Although this catalyst yields polyethylene with a narrow molecular weight distribution in one stage polymerization, it is also possible to produce polyethylene with a wide molecular weight distribution through multistage polymerization. Furthermore, in order to control the molecular weight, it is also possible to change the temperature of the reactor or add hydrogen or an organic compound that is likely to cause chain transfer. Furthermore, it is also possible to conduct the polymerization by combining methods such as adding a titanate ester to adjust the density. Examples of the present invention are shown below, but the present invention is not limited to these examples in any way.

In these examples, MI represents melt index, and according to ASTM D-1238, the temperature was 190°C,
Measured under load 2.16 [9]. F.R.
is the value measured at a temperature of 190℃ and a load of 21.6kg.
It means the quotient divided by , and is one of the measures of molecular weight distribution,
The lower the value, the narrower the molecular weight distribution. The catalyst efficiency is expressed as the amount of polymer produced per unit of Ti+VI, k9. Example 1 1 Hydrocarbon solvent soluble organomagnesium compound (i)
5 days of magnesium powder was added to a 200-liter upper flask that had been purged with nitrogen.

Of a mixture of 20.8 parts of n-butyl chloride and 60 parts of hebutane, 20 parts of the mixture was introduced into the flask. The flask was heated and heated under reflux, and after the reaction started, the remaining n-butyl was removed under reflux for 2 hours. Drip lido,
After finishing, I worshiped for another hour. In addition to this, NC12 (on-
C4 ratio) Add 20% of hebutane containing 12mmol,
By carrying out the reaction for 2 hours, an organic magnesium compound solution was obtained. As a result of analysis, the composition of this complex was found to be AIM-5 (n-C4 day 9), 6-9 ・(0h
-C4 is )o-9, and the organometallic concentration is 0.86 m
It was ol/sleeve. In addition, AIC12 (0n-C4 day 9
) is aluminum powder, AIC13, n-C4 day 90
Synthesis was carried out in hebutane at a molar ratio of 1:2:3.

(b) Synthesis of catalyst component [A] Oxygen and moisture inside a 250' flask equipped with a dropping funnel and a water-cooled reflux condenser were removed by nitrogen substitution, and trichlorosilane 0.1 mol/min was removed under nitrogen atmosphere.
20' of the hebutane solution and 30' of hebutane were charged and the temperature was raised to 70 qo.

Next, 02.33' of the above component (i) and 20 g of hebutane were weighed into the dropping funnel. The mixture was added dropwise to 70 qo over a period of 1 hour over a period of 1 hour, and the mixture was further reacted at this temperature for 1 hour. The reaction solution became a white suspension. To this white suspension, 27.7% of hebutane containing 34% of titanium tetrachloride and 31% of vanadyl trichloride was introduced, and the reaction was carried out at 70 °C for 1 hour. m Catalyst component synthesized by polymerization of ethylene [A]
0.5 I and trioctyl aluminum 0.125 mmo
1 liter of dehydrated and degassed kerosene was placed in an autoclave whose interior was vacuum degassed. Next, 1 hour of hydrogen
After charging the autoclave at 180 q0, ethylene was pressurized at a pressure of 2.0 Mpa, and polymerization was carried out for 30 minutes while keeping the total pressure constant by replenishing ethylene. A polymer with a catalyst efficiency of 850 k9/night (Ti+V) and an MI of 7.
2, FR32, density was 0.970. Example 2~
12 According to the method of Example 1, (i), Sen, Gi shown in Table 1
Catalyst component [A] was synthesized using i) component and conditions.

Using this catalyst component [A], polymerization was carried out according to the method of Example 1 under the conditions indicated by Omotesawa, and the results shown in the table were obtained.

Table 1 Niksen Examples 13 to 16 According to the conditions of Example 1, AIM fleas (n-C4 ratio),
2.(0n-C6 days, 3)3 to 2. Dish mol, SiHC
13. hmol and TIC140.03
hmol and VOC1, *0.03 hmol were reacted to synthesize catalyst component [A].

Using this suspension 1 and AI (C2 day 5) 3, polymerization was carried out according to the method of Example 1 at the temperature shown in the table above and under ethylene pressure, and the results shown in the table were obtained. Table m Example 17 The catalyst component synthesized in Example 13 was left under a nitrogen atmosphere for one month.

Thereafter, polymerization was carried out under the same conditions as in Example 14, and M13.
5, a polymer of FR27 was obtained. Catalyst efficiency is 580k9
/ evening (Tj+V).

Comparative Example 1 Into a nitrogen-substituted 200 flask, NMg
80' of hebutane containing 22 hmol of (C2&)3.(n-C4day9) was charged.

This includes 140.8 hmol of TIC and 130.6 h of VOC.
27 ml of hebutane containing 1 mn was added. This is 1'
Polymerization was carried out in the same manner as in Example 1 except that skin 3.6
FR Shigeru's polymer was obtained. Catalyst efficiency is 34k9/night (T
i+V). Comparative Example 2 The catalyst synthesized in Comparative Example 1 was left in a nitrogen atmosphere for one day, and then polymerized in the same manner.

As a result, the catalyst efficiency was 0.3k9/night (Ti 10V). Examples 18-22 AIM & (n-C6 days, 3) 7 (On-C4) 42.
hmol, SiHC131 hmol and
TIC140.08hmol and VOC130.18h
Catalyst component [A] according to the method of Example 1 using mol
] was synthesized.

Catalyst component [A] 1 secretion and AI (n-C, oH2,) 30.
1 mmol of dehydrated and degassed hebutane (0.6 mmol) was placed in a 1 quart autoclave whose interior was vacuum degassed. Next, hmol of hydrogen and the Q-olefin shown in Table N were introduced, the temperature was raised to 160°C, and 3.5% of ethylene was added. Pressure was applied at a pressure of mmpa. The polymerization was carried out for 30 minutes while maintaining the total pressure by replenishing ethylene, and the results shown in Table W were obtained. Table W Example 23 According to the conditions of Example 1, NMg (n-C4 ratio) 5.
5 [OSiH・(CH3)2]o. 52. enemy hmol,
HSi・C is・CI23hmol and TIC1
40.04 mmol and 130.02 hmol of VOC were reacted to synthesize catalyst component [A].

Using this suspension 1', polymerization was carried out under the conditions of Example 1 to obtain a polymer made from Hada 3.6, FR. Catalyst efficiency is 5
It was 20k9/evening (Ti+V). Example 24 Using 0.5' of the catalyst component [A] synthesized in Example 1 and 0.125 hmol of trioctyl aluminum, 1.8 hol of ethylene was polymerized under the conditions of ethylene pressure of 2 MPa, hydrogen 2 hmol, and temperature of 150 pm. I did it.

Claims (1)

[Claims] 1 (i) General formula MαMgβR^1_pR^2_qX
^1_rX^2_s (in the formula, M is a metal atom of Group I to Group III of the periodic table, β is a number of 1 or more, α, p, q, r, s are 0
or a number greater than or equal to 0, p+q+r+s=mα+2β,0
≦(r+s)/(α+β)≦1, m is the valence of M, R^1, R^2 are hydrocarbon groups having 1 to 20 carbon atoms, which may be the same or different, X^ 1, X^2 is the same or different group, hydrogen atom, OR^3, OSiR^4R^
Represents the group 5R^6, NR^7R^8, SR^9,
R^3, R^7, R^8, R^9 have 1 to 20 carbon atoms
(ii) an organomagnesium compound soluble in a hydrocarbon solvent represented by a hydrocarbon group, R^4, R^5, R^6 each representing a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms; boron, silicon, germanium, tin, lead,
A reactant of one or a mixture of two or more selected from halides of phosphorus, arsenic, antimony, bismuth, and mercury, (iii) a titanium compound and a vanadium compound with a Ti/V molar ratio of 100/1 to 1. /100 reaction product [A] formed by contacting a mixture or reactants,
Or a method of polymerizing ethylene using the reaction product [A] and the organoaluminum compound [B] under one-stage or multi-stage polymerization conditions in the range of 120 to 350°C. 2. The method for polymerizing ethylene according to claim 1, wherein in the organomagnesium compound (i), M is a lithium, beryllium, boron, aluminum or zinc atom. 3. The method for polymerizing ethylene according to claim 1 or 2, wherein in the organomagnesium compound (i), βα is 0.5 to 10. 4 In the organomagnesium compound of (i), α=0
A method for polymerizing ethylene according to claim 1. 5 (i) In the organomagnesium compound, 0<(
The method for polymerizing ethylene according to any one of claims 1 to 4, wherein r+s)/(α+β)≦1. 6. The method for polymerizing ethylene according to any one of claims 1 to 5, wherein (ii) is a boron, silicon or germanium chloride soluble in a hydrocarbon solution. 7. The method of polymerizing ethylene according to claim 6, wherein (ii) is a silicon compound containing at least one chlorine atom and one hydrogen atom. 8. The method for polymerizing ethylene according to any one of claims 1 to 7, wherein (iii) is a titanium compound and a vanadium compound containing a halogen atom. 9 (iii) is TiCl_4 and VOCl_3 or VC
A method for polymerizing ethylene according to claim 8, wherein the ethylene is l_4. 10 In (iii), the (Ti)/V molar ratio is 20/1
9. The method for polymerizing ethylene according to any one of claims 1 to 9, which is 1/20. 11 The reaction of (i) and (ii) is carried out at a temperature of 0 to 150°C with 0.01 to 100 m of component (i) per 1 mol of component (i).
Claims 1 to 10 within the scope of ol.
A method for polymerizing ethylene according to any one of paragraphs. 12 When bringing the reactants (i) and (ii) into contact with (iii), the temperature is -30 to 150°C, Mg/(Ti+V)
Claim 1 in which the molar ratio is in the range of 3 to 500
A method for polymerizing ethylene according to any one of items 1 to 11. 13. When bringing the reactants (i) and (ii) into contact with (iii), the ethylene according to any one of claims 1 to 12 is carried out under conditions where the Ti+V concentration is 4 mol/l or less. How to polymerize. 14. The method for polymerizing ethylene according to any one of claims 1 to 13, wherein the ethylene polymerization is carried out at 150 to 320°C and an ethylene partial pressure of 1.0 to 25 megapascals (Mpa). 15 Using [A] and [B], and (M+Al)/
The method for polymerizing ethylene according to any one of claims 1 to 14, wherein the (Ti+V) molar ratio is from 3/1 to 1000/1. 16. Any one of claims 1 to 15 in which ethylene is polymerized using [A] and [B] in the presence of 100 mol% or less of α-olefin having 3 or more carbon atoms based on ethylene. A method of polymerizing ethylene as described.