JPH0967412A - Production of polyolefin wide in molecular weight distribution - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for simply and easily producing a uniform polyolefin excellent in balance between various kinds of physical properties such as melt elasticity, flow characteristics and mechanical characteristics, and wide in molecular weight distribution. SOLUTION: This method for producing a polyolefin wide in molecular weight distribution comprises continuously polymerizing an olefin in the presence of an olefin polymerization catalyst comprising [A] a transition metal catalyst component and [B] at least a compound selected from the group consisting of (B-1) an organic metal compound and (B-2) a compound capable of reacting with the transition metal catalyst component A to form an ion pair, while changing the concentration of hydrogen in the reaction phase in the same reactor in three or more steps within an average retention time at a time interval below the half of an average retention time in the polymerizer.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a polyolefin having a wide molecular weight distribution and excellent physical properties such as flow characteristics. More specifically, melt elasticity (melt tension, die swell ratio, etc.), flow characteristics (N-
Value, critical shear rate, etc.) and mechanical properties (tensile impact value, resistance to environmental stress cracking, etc.), and a wide range of molecular weight distribution of the polyolefin.

[0002]

2. Description of the Related Art Conventionally, industrial production of polyolefins has been carried out by continuous production, and batch polymerization has never been omitted in industrial production. On the other hand, in order to improve the flow characteristics of polyethylene, for example, a plurality of polyethylenes having different molecular weights are mixed to broaden the molecular weight distribution. Specific methods include a polymer blend method and a multistage polymerization method using a plurality of polymerization vessels,
Since the polymer blending method by mechanical mixing lacks homogeneity, the resulting polyethylene mixture is inferior in physical properties, and thus the continuous multistage polymerization method is said to be preferable. That is, conventionally, a number of continuous two-stage polymerization methods have been proposed in which the polymerization is carried out in two separate reactors to produce two components, thereby broadening the molecular weight distribution. For example, Japanese Patent Publication 60-3908
No. 2, Japanese Patent Publication No. 60-39083, No. 60 Japanese Patent Publication No. 60
-39084, Japanese Patent Publication No. 60-39085,
Japanese Patent Publication No. 46-11349, Japanese Patent Publication No. 48-4271
6, JP-A-51-47079, JP-A-52
No. 19788, JP-A-56-010506, JP-A-59-193913 and the like. A continuous three-stage polymerization method has also been proposed in which the polymerization is carried out by using three separate reactors to form a three-component system to broaden the molecular weight distribution. For example, Japanese Patent Publication 59-10724
Japanese Patent Publication No. 46-11349, Japanese Patent Publication No. 48-
No. 42716, No. 62-25109, No. 62-25105, and No. 62-25106.
JP-A-62-25107, JP-A-62-25107
25108, JP-A-59-227913,
JP 61-130310 A, JP 61-142 A
07, JP-A-2-235947, JP-A-5
No. 7,141,409 is cited.

As described above, according to the continuous polymerization method using a plurality of polymerization vessels, it is possible to broaden the molecular weight distribution to a certain range, but when the molecular weight distribution is wider than a certain level, it is considered as a high molecular weight component and low. Viscosity difference of molecular weight component becomes too large, mixing failure occurs in the extruder during molding, mechanical properties such as impact strength deteriorate, unmelted gel occurs, etc. May occur. This is due to the non-uniformity of the polymer particles obtained. That is, the above-mentioned multistage polymerization method using a plurality of polymerization units is generally superior to the mechanical polymer blending method in the uniformity of the obtained polymer, but it is not always sufficient.

Here, it is assumed that an olefin such as ethylene is polymerized with a heterogeneous solid transition metal catalyst. The polymerization active points are present on the surface of the solid catalyst particles, but it is considered that they are not present on the entire surface of the particle but only in a very small portion on the surface.
When the solid catalyst particles having the polymerization active points thus distributed are continuously polymerized by a plurality of polymerizers, all the active points on one solid catalyst particle are almost the same in the first polymerizer. A polymer having the following properties is produced.
Then, since another polymerization condition is set in the next polymerization vessel, a polymer having physical properties different from that of the first polymer is produced according to another condition set from all polymerization active points. From such a polymerization behavior, it is considered that polymer particles having a multilayer structure are usually obtained in continuous polymerization using a plurality of polymerization vessels. However, in reality, it is said that the polymer chain grows and polymerization proceeds while monomers such as ethylene infiltrate between the active metal / polymer of the polymer grown from the active metal species, so the polymer particles form a simple multilayer structure. It's hard to say. However, in any form, it is considered that the polymer produced in each polymerization vessel forms a block inside the polymer particles produced from one catalyst particle.

The final resin product is obtained by pelletizing such particles by mechanical mixing with a pelletizer, homogenizer or the like, and then molding them with various molding machines. The diameter of the polymer particles obtained in the polymerization vessel is about several mm at the maximum, and the region where the different polymers form blocks and localize within the particles is even smaller. In the case of melt mixing, it is possible to mix to some extent, but it is expected that it will be extremely difficult to mix to an ideal completely uniform state. Therefore, the dispersion state of different polymers in the polymer particles obtained in the polymerization vessel must have some influence on the final product.
It is considered that the more uniform the dispersion of the produced polymer is in the obtained polymer particles to a finer region, the better the physical properties of the resin product obtained by melt-mixing them. As described above, in the multi-stage polymerization method using a plurality of polymerizers, inside each polymer particle, different polymers generated in each polymerizer occupy a certain area to form a block, so that Is not sufficient and even if the polymer particles are mechanically mixed, there is a limit to homogenization, and therefore improvement thereof is desired.

In the case of a multi-stage polymerization method in which a polymer product having a wide molecular weight distribution is produced by producing polymers having different molecular weights in a plurality of polymerization vessels, the difference in melt viscosity due to the difference in molecular weight causes Melt mixing is likely to be further insufficient, and the dispersion of the produced polymer in the polymer particles becomes non-uniform, resulting in significant deterioration of physical properties. In addition, since multiple polymerization reactors are required, not only large capital investment is required, but also the polymerization process is complicated and complicated, and it is extremely difficult to control and control the polymerization system in each reactor. Also exists.

[0007]

SUMMARY OF THE INVENTION In view of the above points, the present invention is homogeneous and melt elasticity (melt tension, die swell ratio, etc.), flow characteristics (N-value, critical shear rate, etc.), mechanical characteristics ( It is an object of the present invention to provide a method for easily and easily producing a polyolefin having a wide molecular weight distribution, which has an excellent balance of various physical properties such as tensile impact value and environmental stress crack resistance.

[0008]

Means for Solving the Problems The inventors of the present invention have made extensive studies in accordance with the above-mentioned object, and as a result, by intermittently or periodically changing the supply amount of hydrogen fed into the same polymerization vessel. The present inventors have found that polyolefins having different molecular weights can be produced on the surface of the same catalyst particle to continuously produce a homogeneous polyolefin having a wide molecular weight distribution, and arrived at the present invention. That is, the first aspect of the present invention is that while changing the hydrogen concentration in the reaction phase in the same polymerization vessel at a time interval of less than 1/2 of the average residence time in the polymerization vessel, while changing it in three or more stages within the average residence time, At least one selected from the group consisting of a metal catalyst component [A], an organometallic compound (B-1) and a compound (B-2) which reacts with the transition metal catalyst component [A] to form an ion pair; The present invention relates to a method for producing a polyolefin having a wide molecular weight distribution, characterized by continuously polymerizing an olefin with an olefin polymerization catalyst comprising a compound [B]. The second aspect of the present invention is to supply the hydrogen gas fed into the same polymerization vessel at a time interval of less than 1/2 of the average residence time in the polymerization vessel,
A compound (B) which reacts with the transition metal catalyst component [A], the organometallic compound (B-1) and the transition metal catalyst component [A] while changing the number of stages in the average residence time by three or more steps (B -2) A method for producing a polyolefin having a wide molecular weight distribution, characterized by continuously polymerizing an olefin with an olefin polymerization catalyst comprising at least one compound [B] selected from the group consisting of A third aspect of the present invention is to change the hydrogen concentration in the reaction phase in the same polymerization vessel at a time interval of less than 1/2 of the average residence time in the polymerization vessel while changing three or more steps within the average residence time,
The present invention relates to a method for producing a polyolefin having a wide molecular weight distribution, which comprises continuously polymerizing an olefin using a solid transition metal catalyst component and an organometallic compound as a catalyst. A fourth aspect of the present invention is to change the amount of hydrogen gas fed into the same polymerization vessel in three stages or more within the average retention time at a time interval of less than 1/2 of the average retention time in the polymerization vessel. The present invention relates to a method for producing a polyolefin having a wide molecular weight distribution, characterized by continuously polymerizing an olefin by using a solid transition metal catalyst component and an organometallic compound as a catalyst.
Furthermore, a fifth invention of the present invention is the polyolefin of wide molecular weight distribution according to any one of the first to fourth inventions, characterized in that the hydrogen concentration or the hydrogen gas supply amount is changed discontinuously. It relates to a manufacturing method.

As described above, when the polymerization active points are present only in a very small portion of the catalyst surface, polyolefins having different molecular weights, such as polyethylene, form blocks mainly at the polymerization active points. According to the method of the present invention, a resin product obtained by mechanically melt-mixing with a pelletizer or the like has a wide molecular weight distribution, but a uniform product can be obtained. The reason is not clear,
It is presumed that, since each block composed of polyolefins having different molecular weights is relatively small, the dispersion state of the polymers having different molecular weights in the polymer particles becomes uniform even in a finer region.

The present invention will be described in more detail below. In the present invention, from the group consisting of the transition metal catalyst component [A], the organometallic compound (B-1) and the compound (B-2) which reacts with the transition metal catalyst component [A] to form an ion pair. An olefin is continuously polymerized by an olefin polymerization catalyst composed of at least one compound [B] selected. As the transition metal catalyst component [A], there are group IV to VI of the periodic table.
Compounds of Group II, preferably Group IV to Group VI can be used, and specific examples thereof include Ti, Zr, Hf, V, Cr,
Compounds such as Mo can be mentioned. This [A] also includes a group IVB transition metal compound containing a ligand having a cyclopentadienyl skeleton. The compound [B] used in combination with the transition metal catalyst component [A] is a compound (B-2) which reacts with the organometallic compound (B-1) and the transition metal catalyst component [A] to form an ion pair. ). These can be used alone or as a mixture. In the present invention, any olefin polymerization catalyst can be used as long as it has the above-mentioned constitution and hydrogen exhibits a chain transfer action in olefin polymerization. Particularly in the case of a heterogeneous catalyst, the polymerization active sites are localized, so that the effect of the present invention is remarkably exhibited.

First, of the [A] transition metal catalyst components, a transition metal compound containing a ligand having a cyclopentadienyl skeleton will be described. The transition metal compound of Group IVB of the periodic table containing a ligand having a cyclopentadienyl skeleton used in the present invention is not particularly limited and is represented by the following general formula [I]. ML _x ······ [I] In the above formula, M is a transition metal atom selected from Group IVB of the periodic table, specifically zirconium, titanium or hafnium, preferably zirconium. L is a ligand that coordinates to a transition metal, at least one of which has a cyclopentadienyl skeleton, and the other L has a carbon number of 1
To 12 hydrocarbon groups, alkoxy groups, aryloxy groups,
A trialkylsilyl group, an SO ₃ R group (wherein R is a hydrocarbon group having 1 to 8 carbon atoms which may have a substituent such as halogen), a halogen atom or a hydrogen atom, and x is a transition metal Valence.

Examples of the ligand having a cyclopentadienyl skeleton include, in addition to the cyclopentadienyl group, for example, a methylcyclopentadienyl group, a dimethylcyclopentadienyl group, a trimethylcyclopentadienyl group, a tetramethylcyclopenta group. Dienyl group, pentamethylcyclopentadienyl group, ethylcyclopentadienyl group, methylethylcyclopentadienyl group, propylcyclopentadienyl group, methylpropylcyclopentadienyl group,
Alkyl-substituted cyclopentadienyl group such as butylcyclopentadienyl group, methylbutylcyclopentadienyl group, hexylcyclopentadienyl group or indenyl group, 4,5,6,7-tetrahydroindenyl group, fluorenyl group, etc. Can be illustrated. These groups may be substituted with a trialkylsilyl group or a halogen atom.

Of these ligands having a cyclopentadienyl skeleton, an alkyl-substituted cyclopentadienyl group is particularly preferable. In addition, the compound represented by the above general formula [I] has a ligand having a cyclopentadienyl skeleton 2
When more than one is included, the ligand having two cyclopentadienyl skeletons is an alkylene group such as ethylene or propylene, a substituted alkylene group such as isopropylidene or diphenylmethylene, a silylene group, or a dimethylsilylene group, They may be bonded to each other via a substituted silylene group such as a diphenylsilylene group or a methylphenylsilylene group.

Specific examples of the ligand L other than the ligand having a cyclopentadienyl skeleton include the following. That is, examples of the hydrocarbon group having 1 to 12 carbon atoms include an alkyl group, a cycloalkyl group, an aryl group and an aralkyl group, and more specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group as the alkyl group. Group, butyl group, etc., cycloalkyl group, cyclopentyl group, cyclohexyl group, etc., aryl group, phenyl group, tolyl group, etc., and aralkyl group, benzyl group, neophyll group, etc. Examples of the alkoxy group include a methoxy group, ethoxy group, butoxy group and the like, examples of the aryloxy group include a phenoxy group and the like, and examples of the halogen include fluorine, chlorine, bromine, iodine and the like. As the ligand represented by SO ₃ R, a p-toluenesulfonate group,
Examples thereof include a methanesulfonate group and a trifluoromethanesulfonate group.

The transition metal compound containing at least one ligand having a cyclopentadienyl skeleton as described above is
For example, when the valence of the transition metal is 4, it is represented by the following general formula [II]. (R ₂ ) _k (R ₃ ) _l (R ₄ ) _m (R ₅ ) _n M ········ [II] In the above formula, M is the transition metal atom, and R ₂ is cyclopentadienyl. If it is a group (ligand) having a skeleton,
R ₃ , R ₄ and R ₅ are each a group having a cyclopentadienyl skeleton, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkoxy group, an aryloxy group, a trialkylsilyl group, an SO ₃ R group as described above. , A halogen atom or a hydrogen atom, k is an integer of 1 or more, and k +
1 + m + n = 4. In the present invention, the above general formula [II]
In the above, a metallocene compound in which two of the groups R ₂ to R ₅ (for example, R ₂ and R ₃ ) are groups having a cyclopentadienyl skeleton is preferably used. In this case, as described above, two groups having a cyclopentadienyl skeleton may be bonded via various divalent groups.

Specific examples of the metallocene compound in which the transition metal is zirconium will be shown below. That is,
Bis (indenyl) zirconium dichloride, bis (indenyl) zirconium dibromide, bis (indenyl) zirconium bis (p-toluenesulfonato), bis (4,5,6,7-tetrahydroindenyl) zirconium dichloride, bis (fluorenyl) Zirconium dichloride, ethylenebis (indenyl) zirconium dichloride, ethylenebis (indenyl) zirconium dibromide, ethylenebis (indenyl) dimethylzirconium, ethylenebis (indenyl) diphenylzirconium, ethylenebis (indenyl) methylzirconium monochloride, ethylenebis (indenyl) ) Zirconium bis (methane sulfonate), ethylene bis (indenyl) zirconium bis (p-toluene sulfonate),
Ethylene bis (indenyl) zirconium bis (trifluoromethanesulfonato), ethylene bis (4,5,6,
7-Tetrahydroindenyl) zirconium dichloride, isopropylidene (cyclopentadienyl-fluorenyl) zirconium dichloride, isopropylidene (cyclopentadienyl-methylcyclopentadienyl) zirconium dichloride, dimethylsilylenebis (cyclopentadienyl) zirconium dichloride , Dimethylsilylenebis (methylcyclopentadienyl) zirconium dichloride, dimethylsilylenebis (dimethylcyclopentadienyl) zirconium dichloride, dimethylsilylenebis (trimethylcyclopentadienyl) zirconium dichloride, dimethylsilylenebis (indenyl) zirconium dichloride, dimethyl Silylenebis (indenyl) zirconium bis (trifluoromethanesulfonato), dimethyl Shirirenbisu (4, 5,
6,7-Tetrahydroindenyl) zirconium dichloride, dimethylsilylene (cyclopentadienyl-fluorenyl) zirconium dichloride, diphenylsilylenebis (indenyl) zirconium dichloride, methylphenylsilylenebis (indenyl) zirconium dichloride, bis (cyclopentadienyl) Zirconium dichloride, bis (cyclopentadienyl) zirconium dibromide, bis (cyclopentadienyl) methylzirconium monochloride, bis (cyclopentadienyl)
Ethyl zirconium monochloride, bis (cyclopentadienyl) cyclohexyl zirconium monochloride,
Bis (cyclopentadienyl) phenyl zirconium monochloride, bis (cyclopentadienyl) benzyl zirconium monochloride, bis (cyclopentadienyl) zirconium monochloride monohydride, bis (cyclopentadienyl) methylzirconium monohydride, bis (Cyclopentadienyl) dimethylzirconium, bis (cyclopentadienyl) diphenylzirconium, bis (cyclopentadienyl) dibenzylzirconium, bis (cyclopentadienyl) zirconium methoxy chloride, bis (cyclopentadienyl)
Zirconium ethoxy chloride, bis (cyclopentadienyl) zirconium bis (methane sulfonate), bis (cyclopentadienyl) zirconium bis (p-toluene sulfonate), bis (cyclopentadienyl) zirconium bis (trifluoromethane sulfonate) ), Bis (methylcyclopentadienyl) zirconium dichloride, bis (dimethylcyclopentadienyl) zirconium dichloride, bis (dimethylcyclopentadienyl)
Zirconium ethoxy chloride, bis (dimethylcyclopentadienyl) zirconium bis (trifluoromethanesulfonato), bis (ethylcyclopentadienyl)
Zirconium dichloride, bis (methylethylcyclopentadienyl) zirconium dichloride, bis (propylcyclopentadienyl) zirconium dichloride, bis (methylpropylcyclopentadienyl) zirconium dichloride, bis (butylcyclopentadienyl) zirconium dichloride, bis (Methylbutylcyclopentadienyl) zirconium dichloride, bis (methylbutylcyclopentadienyl) zirconium bis (methanesulfonato), bis (trimethylcyclopentadienyl) zirconium dichloride, bis (tetramethylcyclopentadienyl) zirconium dichloride , Bis (pentamethylcyclopentadienyl) zirconium dichloride, bis (hexylcyclopentadienyl) zirconium dichloride, bi Such as (trimethylsilyl cyclopentadienyl) zirconium dichloride.
In the above example, the disubstituted product having two groups having a cyclopentadienyl skeleton is 1,2- and 1,3.
-Including substitutions, tri-substitutions being 1,2,3- and 1,2,4
-Including substitutions. The alkyl group such as propyl and butyl includes isomers such as n-, iso-, sec- and tert-.

The zirconium compound may be replaced with zirconium by titanium or hafnium. Among these, bis (cyclopentadienyl) zirconium dichloride, bis (methylcyclopentadienyl) zirconium dichloride, bis (pentamethylcyclopentadienyl) zirconium dichloride, bis (indenyl) zirconium dichloride and the like are particularly preferable.

As the organometallic compound of [B] (B-1),
Examples include organic aluminum compounds and organic aluminum oxy compounds. First, of the above, the organoaluminum oxy compound will be described in detail. The organoaluminum oxy compound used in the present invention may be a conventionally known aluminoxane or a benzene-insoluble organoaluminum oxy compound as exemplified in JP-A-2-78687.

The above aluminoxane can be produced, for example, by the following method. (1) Carbonization of a compound having adsorbed water or a salt having water of crystallization, such as magnesium chloride hydrate, copper sulfate hydrate, aluminum sulfate hydrate, nickel sulfate hydrate, and ceric chloride hydrate A method in which an organoaluminum compound such as trialkylaluminum is added to a suspension obtained by suspending the suspension in a hydrogen medium to cause a reaction, and the suspension is recovered as a hydrocarbon solution. (2) A method in which water, ice, or steam is directly applied to an organoaluminum compound such as trialkylaluminum in a medium such as benzene, toluene, ethyl ether, or tetrahydrofuran to recover it as a hydrocarbon solution. (3) A method of reacting an organoaluminum compound such as trialkylaluminum with an organotin oxide such as dimethyltin oxide or dibutyltin oxide in a medium such as decane, benzene, or toluene. The aluminoxane may contain a small amount of an organometallic compound component. Alternatively, the solvent or unreacted organoaluminum compound may be distilled off from the recovered solution of the aluminoxane, and then the aluminoxane may be redissolved in the solvent.

Specific examples of the organoaluminum compound used when preparing the aluminoxane include trimethylaluminum, triethylaluminum, tripropylaluminum, triisopropylaluminum and tri-aluminum.
trialkylaluminums such as n-butylaluminum, triisobutylaluminum, tri-sec-butylaluminum, tri-tert-butylaluminum, tripentylaluminum, trihexylaluminum, trioctylaluminum, tridecylaluminum;
Tricycloalkylaluminum such as tricyclohexylaluminum and tricyclooctylaluminum;
Dialkyl aluminum halides such as dimethyl aluminum chloride, diethyl aluminum chloride, diethyl aluminum bromide and diisobutyl aluminum chloride; Dialkyl aluminum hydrides such as diethyl aluminum hydride and diisobutyl aluminum hydride; Dialkyl aluminum alkoxides such as dimethyl aluminum methoxide and diethyl aluminum ethoxide; diethyl Examples thereof include dialkylaluminum aryloxides such as aluminum phenoxide. Of these, trialkylaluminums and tricycloalkylaluminums are particularly preferred. The above organoaluminum compounds can be used alone or in combination. Further, these organoaluminum compounds can be used as they are as the organometallic compound (B-1).

Solvents used for obtaining a solution of aluminoxane include benzene, toluene, xylene, cumene,
Aromatic hydrocarbons such as cymene, pentane, hexane, heptane, octane, decane, dodecane, hexadecane,
Aliphatic hydrocarbons such as octadecane, cyclopentane,
Alicyclic hydrocarbons such as cyclohexane, cyclooctane and methylcyclopentane, petroleum fractions such as gasoline, kerosene and light oil, or halides of the above aromatic hydrocarbons, aliphatic hydrocarbons and alicyclic hydrocarbons, especially chlorine. And hydrocarbon solvents such as bromine and bromide. In addition, ethers such as ethyl ether and tetrahydrofuran can also be used. Of these solvents, aromatic hydrocarbons are particularly preferable.

Transition metal catalyst component used in the present invention
Examples of the compound (B-2) which reacts with [A] to form an ion pair include those disclosed in JP-A-1-501950 and JP-A-1-50.
2036, JP 3-179005 A, JP 3-179006 A, JP 3-207703 A, JP 3-207704 A, US Pat. No. 54.
Examples thereof include Lewis acids, ionic compounds, borane compounds and carborane compounds described in No. 7,718. The components (B-2) described below can be used as a mixture of two or more kinds.

Examples of the Lewis acid include magnesium-containing Lewis acid, aluminum-containing Lewis acid, boron-containing Lewis acid and the like, and among these, boron-containing Lewis acid is preferable. The Lewis acid containing a boron atom can be represented by the following general formula [III]. B (R ₆ ) (R ₇ ) (R ₈ ) ······· [III] In the above formula, R ₆ , R ₇ and R ₈ are each a fluorine atom,
A phenyl group which may have a substituent such as a methyl group and a trifluoromethyl group, or a fluorine atom is shown. Specific examples of the compound represented by the above general formula include trifluoroboron, triphenylboron, tris (4-fluorophenyl) boron, tris (3,5-difluorophenyl).
Boron, tris (4-fluoromethylphenyl) boron, tris (pentafluorophenyl) boron, tris (p-tolyl) boron, tris (o-tolyl) boron,
Examples include tris (3,5-dimethylphenyl) boron. Of these, tris (pentafluorophenyl) boron is particularly preferable.

The ionic compound used as the component (B-2) in the present invention is a salt composed of a cation and an anion. The anion is the transition metal catalyst component [A].
It exhibits the action of cationizing the transition metal catalyst component by reacting with and forming an ion pair to stabilize the transition metal cation species. As such anions, there are organic boron compound anions, organic arsenic compound anions, organic aluminum compound anions, and the like, and those which are relatively bulky and stabilize the transition metal cation species are preferable. Examples of the cation include a metal cation, an organometallic cation, a carbonium cation, an oxonium cation, a sulfonium cation, a phosphonium cation, and an ammonium cation. More specifically, examples thereof include triphenylcarbenium cation, tributylammonium cation, N, N-dimethylammonium cation, and ferrocenium cation.

The ionic compound used in the present invention is preferably one containing a boron compound as an anion. Specifically, examples of compounds containing a trialkyl-substituted ammonium salt include, for example, triethylammonium tetra (phenyl) boron, tripropylammonium tetra (phenyl) boron, tri (n-butyl) ammonium tetra (phenyl) boron, and trimethylammonium tetra. (P-Tolyl) boron, trimethylammonium tetra (o-tolyl) boron, tributylammonium tetra (pentafluorophenyl) boron, tripropylammonium tetra (o, p-dimethylphenyl) boron, tributylammonium tetra (m, m-)
Dimethylphenyl) boron, tributylammonium tetra (p-trifluoromethylphenyl) boron, tri (n-butyl) ammonium tetra (o-tolyl) boron, tri (n-butyl) ammonium tetra (4-fluorophenyl) boron, etc. Examples of compounds containing N, N-dialkylanilinium salts include N, N
-Dimethylanilinium tetra (phenyl) boron,
N, N-diethylanilinium tetra (phenyl) boron, N, N-2,4,6-pentamethylanilinium tetra (phenyl) boron and the like can be mentioned. Examples of compounds containing a dialkylammonium salt include di (n -Propyl) ammonium tetra (pentafluorophenyl) boron, dicyclohexylammonium tetra (phenyl) boron, etc., and examples of compounds containing a triarylphosphonium salt include triphenylphosphonium tetra (phenyl) boron and tri (methylphenyl) boron.
Examples thereof include phosphonium tetra (phenyl) boron and tri (dimethylphenyl) phosphonium tetra (phenyl) boron. Further, in the present invention, as the ionic compound containing a boron atom, triphenylcarbenium tetrakis (pentafluorophenyl) borate, N, N-dimethylanilinium tetrakis (pentafluorophenyl) borate, ferrocenium tetra (pentaphenyl) Also included are fluorophenyl) borate and the like.

The following ionic compounds can also be exemplified. In the ionic compounds listed below, the cation is tri (n-butyl) ammonium, but the cation is not limited to this (the same applies hereinafter). That is, bis [tri (n-butyl) ammonium] nonaborate, bis [tri (n-butyl) ammonium] decaborate, bis [tri (n-butyl) ammonium] undecaborate, bis [tri (n-butyl)]
Ammonium] dodecaborate, bis [tri (n-butyl) ammonium] decachlorodecaborate, bis [tri (n-butyl) ammonium] dodecachlorododecaborate, tri (n-butyl) ammonium-1-carbadecaborate, tri (N-Butyl) ammonium-1-
Carbaundecaborate, tri (n-butyl) ammonium-1-carbadodecaborate, tri (n-butyl)
Ammonium-1-trimethylsilyl-1-carbadecaborate, tri (n-butyl) ammonium bromo-1
-Carbadodecaborate etc. can be mentioned.

Further, in the present invention, the component (B-2)
Examples thereof include borane compounds and carborane compounds. First, borane and carborane complex compounds, and salts containing carborane anions are used,
For example, decaborane (14), 7,8-dicarbaundecaborane (13), 2,7-dicarbaundecaborane (1
3), undeca hydride-7,8-dimethyl-7,8
-Dicarbound Decaborane, Dodeca Hydride-11
-Methyl-2,7-dicarbaundecaborane, tri (n
-Butyl) ammonium-6-carbadecaborate (1
4), tri (n-butyl) ammonium-6-carbadecaborate (12), tri (n-butyl) ammonium-7-carbaundecaborate (13), tri (n-butyl) ammonium-7,8- Dicarbaundecaborate (12), tri (n-butyl) ammonium-2,9
-Dicarbaundecaborate (12), tri (n-butyl) ammonium dodecahydride-8-methyl-
7,9-Dicarbaundecaborate, tri (n-butyl) ammonium undecahydride-8-ethyl-
7,9-Dicarbaundecaborate, tri (n-butyl) ammonium undecahydride-8-butyl-
7,9-Dicarbaundecaborate, tri (n-butyl) ammonium undecahydride-8-allyl-
7,9-Dicarbaundecaborate, tri (n-butyl) ammonium undecahydride-9-trimethylsilyl-7,8-dicarbaundecaborate, tri (n-butyl) ammonium undecahydride
4,6-dibromo-7-carbaundecaborate and the like can be mentioned. In addition, carborane and salts of carborane are used, and 4-carbanonaborane (14), 1,3-dicarbanonaborane (13), 6,9-dicarbadecaborane (14), dodecahydride-1-phenyl-1. ,
Examples thereof include 3-dicarbanonaborane, dodecahydride-1-methyl-1,3-dicarbanonaborane, and undecahydride-1,3-dimethyl-1,3-dicarbanonaborane.

Further, the following compounds can be exemplified. That is, as salts of metal carboranes and metal borane anions, for example, tri (n-butyl) ammonium bis (nonahydride-1,3-dicarbanonaborate) cobaltate (III), tri (n-butyl)
Ammonium bis (undecahydride-7,8-dicarbaundecaborate) ferrate (ferrate) (II
I), tri (n-butyl) ammonium bis (undecahydride-7,8-dicarbaundecaborate) cobaltate (III), tri (n-butyl) ammonium bis (undecahydride-7,8-dicarbaundeca) Borate) nickelate (III), tri (n-butyl) ammonium bis (undecahydride-7,
8-dicarbaundecaborate) cuprate (cuprate) (III), tri (n-butyl) ammonium bis (undecahydride-7,8-dicarbaundecaborate) aureate (III), Tri (n-butyl) ammonium bis (nonahydride-7,8-
Dimethyl-7,8-dicarbaundecaborate) ferrate (III), tri (n-butyl) ammonium bis (nonahydride-7,8-dimethyl-7,8-dicarbaundecaborate) chromate (chromate) ( II
I), tri (n-butyl) ammonium bis (tribromooctahydride-7,8-dicarbaundecaborate) cobaltate (III), tri (n-butyl) ammonium bis (dodecahydridedicarbadodecaborate) cobaltate (III) ), Bis [tri (n-butyl) ammonium] bis (dodecahydride dodecaborate) nickelate (III), tris [tri (n-butyl) ammonium] bis (undecahydride-7)
-Carbaundecaborate) chromate (III), bis [tri (n-butyl) ammonium] bis (undecahydride-7-carbaundecaborate) manganate (IV), bis [tri (n-butyl) ammonium] Bis (undecahydride-7-carbaundecaborate) cobaltate (III), bis [tri (n-butyl)]
Ammonium] bis (undecahydride-7-carbaundecaborate) nickelate (IV) and the like.

Preferred examples of the olefin polymerization catalyst used in the present invention include Ti as the transition metal catalyst component [A].
And / or V compound and an organometallic compound (B-1)
There is a solid Ziegler catalyst composed of an organoaluminum compound as Among them, particularly preferable solid transition metal catalyst components for olefin polymerization include those containing at least titanium and / or vanadium and magnesium. Next, the solid transition metal catalyst component will be described.

As described above, as the olefin polymerization catalyst, a solid catalyst component containing titanium and magnesium, a solid catalyst component containing vanadium and magnesium, or titanium, vanadium and magnesium used in a conventionally known Ziegler type catalyst. It is possible to use a solid catalyst component containing For example, metal magnesium, magnesium hydroxide, magnesium carbonate, magnesium oxide, magnesium chloride, etc., or a double salt, double oxide, carbonate, chloride or hydroxide containing magnesium with an element selected from silicon, aluminum and calcium. Etc., and inorganic solid compounds containing magnesium such as those obtained by treating or reacting these inorganic solid compounds with oxygen-containing compounds, sulfur-containing compounds, aromatic hydrocarbons, halogen-containing substances, titanium compounds and / or vanadium compounds. Examples thereof include those obtained by carrying a known method.

Examples of the oxygen-containing compounds include water; polysiloxanes; organic oxygen-containing compounds such as alcohols, phenols, ketones, aldehydes, carboxylic acids, esters and acid amides; metal alkoxides; inorganic compounds such as metal oxychlorides. An oxygen compound can be illustrated. Examples of the sulfur-containing compound include organic sulfur compounds such as thiol and thioether, and inorganic sulfur compounds such as sulfur dioxide, sulfur trioxide and sulfuric acid. Examples of aromatic hydrocarbons include various monocyclic or polycyclic aromatic hydrocarbons such as benzene, toluene, xylene, anthracene, and phenanthrene. Examples of the halogen-containing substance include chlorine, hydrogen chloride, metal chlorides and organic halides.

Examples of the titanium compound include titanium halides, alkoxy halides, alkoxides,
Examples thereof include halogenated oxides. Of these, a tetravalent titanium compound and a trivalent titanium compound are preferable, and the tetravalent titanium compound is specifically defined by the general formula Ti (OR) _n X _4-n (where R is the number of carbon atoms). 1 to 20 represents a hydrocarbon residue such as an alkyl group, an aryl group or an aralkyl group, X represents a halogen element, and n is a number in the range of 0 ≦ n ≦ 4). , Specifically, titanium tetrachloride, titanium tetrabromide, titanium tetraiodide, monomethoxytrichlorotitanium, dimethoxydichlorotitanium, trimethoxymonochlorotitanium, tetramethoxytitanium, monoethoxytrichlorotitanium, diethoxydichlorotitanium, triethoxymonochlorotitanium. Titanium, tetraethoxy titanium, monoisopropoxy trichloro titanium,
Diisopropoxydichlorotitanium, triisopropoxymonochlorotitanium, tetraisopropoxytitanium, monobutoxytrichlorotitanium, dibutoxydichlorotitanium, tributoxymonochlorotitanium, tetrabutoxytitanium, monopentoxytrichlorotitanium, monophenoxytrichlorotitanium, diphenoxydichloro. Titanium, triphenoxy monochloro titanium, tetraphenoxy titanium, etc. can be mentioned. The trivalent titanium compound has a general formula of Ti (OR) _m X _4-m (wherein R is a carbon number of 1 to 2).
0 represents a hydrocarbon residue such as an alkyl group, an aryl group or an aralkyl group, and X represents a halogen element. m is 0
It is a number in the range of <m <4. And a trivalent titanium compound obtained by reducing the tetravalent halogenated alkoxytitanium represented by the formula (4) with hydrogen, aluminum, titanium or an organometallic compound of a metal of Group I to III of the periodic table.

Of the above titanium compounds, tetravalent titanium compounds are particularly preferable. Specific examples of these catalysts include, for example, MgO-RX-TiCl ₄ system (Japanese Patent Publication No. 51-
3514 _{JP), Mg-SiCl 4 -ROH-} TiCl 4 type (JP-B 50-23864 discloses), MgCl ₂ -Al (O
R) ₃ -TiCl ₄ system (Japanese Patent Publication No. 51-152, Japanese Patent Publication No. 52-15111), MgCl ₂ -SiCl ₄ -ROH
-TiCl ₄ system (JP-A-49-106581), Mg
(OOCR) ₂ -Al (OR) ₃ -TiCl ₄ system (Japanese Patent Publication No. 52-1
1710 JP), Mg-POCl ₃ -TiCl ₄ system (JP-B 51-153 discloses), MgCl ₂ -AlOCl-TiCl ₄ type (JP-B 54-15316 discloses), MgCl ₂ -Al (O
R) _n X _3-n -Si (OR ') _m X _4-m -TiCl ₄ system (JP _-A- 56)
-95909 discloses), MgCl ₂ -ROH- siloxane _{-Ti (OR) m X 4-} m -TiCl 4 system (Japanese Patent Application No. 5-28409
5 JP), MgCl ₂ -ROH- surfactant -Ti (OR)
_m X _4-m -TiCl ₄ system (Japanese Patent Application No. 5-2844096)
Preferred examples include those in which an organoaluminum compound is combined with a solid catalyst component such as (in the above formula, R and R ′ are organic residues, and X is a halogen atom).

Examples of the vanadium compound include tetravalent vanadium compounds such as vanadium tetrachloride, vanadium tetrabromide and vanadium tetraiodide, and pentavalent vanadium compounds such as vanadium oxytrichloride and orthoalkylvanadate.
Examples thereof include trivalent vanadium compounds such as vanadium trichloride and vanadium triethoxide. The vanadium compound is used alone or in combination with the titanium compound.

Another example of the catalyst system is a catalyst system in which a reaction product of an organomagnesium compound such as a so-called Grignard compound and a titanium compound and / or a vanadium compound is used as a solid catalyst component, and an organoaluminum compound is combined therewith. Can be illustrated. Examples of the organomagnesium compound include the general formula RMgX,
A magnesium compound represented by R ₂ Mg, RMg (OR) or the like (wherein R represents an organic residue having 1 to 20 carbon atoms, X represents a halogen atom), an ether complex thereof, or an organomagnesium compound thereof. In addition, a modified organic metal compound such as organic sodium, organic lithium, organic potassium, organic boron, organic calcium, or organic zinc can be used. Specific examples of the catalyst systems, for example, RMgX-TiCl ₄ type (JP-B 50-39470 discloses), RMgX- phenol -TiCl ₄ system (JP-B 54-12953 JP)
RMgX-halogenated phenol-TiCl ₄ system (Japanese Patent Publication 5)
No. 4-12954), RMgX—CO ₂ —TiCl ₄ system (Japanese Patent Laid-Open No. 57-73009), and the like, in which an organoaluminum compound is combined with a solid catalyst component.

As another example of the catalyst system, the solid catalyst component contains inorganic oxides such as SiO ₂ , Al ₂ O ₃ and SiO ₂ .Al ₂ O ₃ and the above titanium and / or vanadium and magnesium. A solid substance obtained by contacting with a solid catalyst component is used, and an organoaluminum compound in combination therewith can be exemplified. As the inorganic oxide, the above-mentioned SiO ₂ , Al ₂ O ₃ and SiO ₂ .Al can be used.
_In addition to ₂ O _3, etc., CaO, B ₂ O ₃ , SnO _2, etc. can be mentioned, and a double oxide of these oxides can also be used. In order to bring these various inorganic oxides into contact with the solid catalyst containing titanium and / or vanadium and magnesium, known methods can be adopted. That is, in the presence or absence of an organic solvent such as an inert hydrocarbon, alcohols, phenols, ethers, ketones, esters, amines, nitriles, or a mixture thereof, at a temperature of 20 to 400 ° C., Preferably, a method of reacting at 50 to 300 ° C. for usually 5 minutes to 20 hours is used. Specific examples of the above catalyst system include, for example, SiO ₂ —ROH—MgCl ₂ —TiCl ₄ (JP-A-56-47407), SiO ₂ —ROR′-Mg.
O-AlCl ₃ -TiCl ₄ (JP 57-187305 _{JP), SiO 2 -MgCl 2 -Al (} OR) 3 -TiCl 4 -Si (O
R ') ₄ (Japanese Patent Laid-Open No. 58-21405), SiO ₂ -Ti
_{Cl 4 -R n AlCl 3-n} -MgCl 2 -Al (OR ') n Cl 3-n ( JP-A 3-35004 _{discloses), SiO 2 -TiCl 4 -R n} A
lCl _3-n -MgCl ₂ -Al (OR ') _n Cl _3-n -Si (OR'') _m
Cl _4-m (Japanese Patent Laid-Open No. 3-64306), SiO ₂ -Mg
_{Cl 2 -Al (OR ') n} Cl 3-n -Ti (OR'') 4 -R n AlCl
_3-n (JP-A-3-153707), SiO ₂ -Mg
_{Cl 2 -Al (OR ') n} Cl 3-n -Ti (OR'') n Cl 4-n -R n A
lCl _3-n (JP-A-3-18504), SiO ₂ -Ti
_{Cl 4 -R n AlCl 3-n} -MgCl 2 -Al (OR ') n Cl 3-n -
R ″ _m Si (OR ′ ″) _n X _{4- (m + n)} (JP-A-4-26140 ₎
8 _{JP), SiO 2 -R n MgX 2} -n -Al (OR ') n Cl 3-n
_{-Ti (OR '') n Cl} 4-n -R '''OH-R n AlX 3-n ( JP-A-5-117316), SiO ₂ -MgCl ₂ -Al
_{(OR ') n Cl 3-} n -Ti (OR'') n Cl 4-n -R''' OH-
An organic aluminum compound was combined with R _n AlCl _3-n (JP-A-5-194634) (wherein R, R ′, R ″, and R ″ ′ represent a hydrocarbon residue) and the like. I can list things.

In these catalyst systems, a titanium compound and / or a vanadium compound can be used as an adduct with an organic carboxylic acid ester, and the above-mentioned inorganic solid compound containing magnesium is contact-treated with the organic carboxylic acid ester. It can be used later. further,
Organoaluminum compounds can also be used as adducts with organic carboxylic acid esters. Also, in all cases it is possible to use catalyst systems prepared in the presence of organic carboxylic acid esters. Examples of the organic carboxylic acid ester used here include various esters of aliphatic, alicyclic, and aromatic carboxylic acids, and aromatic carboxylic acid esters having 8 to 12 carbon atoms are preferably used. Specific examples thereof include alkyl esters of benzoic acid, anisic acid, toluic acid such as methyl and ethyl. The solid catalyst component may be subjected to prepolymerization before being fed to the reaction system and used in the form of a so-called prepolymer coated with a polymer.

In the present invention, the organoaluminum compound which can be used together with the above solid catalyst component containing at least titanium and / or vanadium and magnesium means an organoaluminum having at least one aluminum-carbon atom bond in the molecule. Refers to a compound. For example, (i) the general formula R _m Al (OR ′) _n H _p X
_q (where R and R ′ are usually 1 to 15 carbon atoms,
It is preferably a hydrocarbon group containing 1 to 4 groups such as an alkyl group, an aryl group, an alkenyl group and a cycloalkyl group, and in the case of an alkyl group, methyl, ethyl, propyl, isopropyl, isobutyl, sec-butyl, tert. −
Butyl, hexyl, octyl and the like can be mentioned. R and R'may be the same or different. X represents a halogen atom, m, n, p and q are 0 <m ≦ 3,
It is a number in the range of 0 ≦ n <3, 0 ≦ p <3 and 0 ≦ q <3 and satisfying m + n + p + q = 3. ), An organoaluminum compound represented by
A complex alkyl of a Group I metal of the periodic table and aluminum represented by R ₄ (wherein M is a metal selected from Li, Na or K, and R is the same hydrocarbon group as described above). A compound etc. can be mentioned.

Examples of the organoaluminum compound belonging to the above (i) include, for example, the general formula R _m Al (OR ′) _3-m (wherein R and R ′ are the same hydrocarbon groups as described above. M is preferably 1.5 ≦ m ≦ 3), R _m AlX _3-m (wherein R is the same hydrocarbon group as described above, and m is preferably 0 <m <3). ), The general formula R _m AlH _3-m (wherein R is the same hydrocarbon group as described above, and m is preferably in the range of 2 ≦ m <3) and the general formula R _m Al (OR ′. ) _n X _q (wherein R and R ′ are the same hydrocarbon groups as described above. X is a halogen atom, and m, n and q are preferably 0 <m ≦ 3, 0 ≦ n <3, (The number is within the range of 0 ≦ q <3 and satisfies m + n + q = 3.)
And the like can be exemplified.

Specific examples of the organoaluminum compound belonging to (i) include trimethylaluminum, triethylaluminum, triisopropylaluminum, triisobutylaluminum, tri-sec-butylaluminum, tri-tert-butylaluminum, trihexylaluminum, Trialkylaluminums such as trioctylaluminum; Trialkenylaluminums; Dialkylaluminium alkoxides such as diethylaluminum ethoxide and dibutylaluminum butoxide; Alkylaluminum sesquialkoxides such as ethylaluminum sesquiethoxide and butylaluminum sesquibutoxide, and R _2.5 al (OR) partially alkylaluminum is alkoxylated with an average composition represented by like _0.5; Jiechirua Dialkyl aluminum halides such as minium chloride, dibutyl aluminum chloride and diethyl aluminum bromide; partially halogenated alkyl aluminums such as ethyl aluminum sesquichloride, butyl aluminum sesquichloride and ethyl aluminum sesquibromide; diethyl Partially hydrogenated alkylaluminum such as aluminum hydride, dialkylaluminum hydride such as dibutylaluminum hydride and alkylaluminum dihydride such as ethylaluminum dihydride and propylaluminum dihydride; ethylaluminum ethoxy chloride, butylaluminum butoxycyclolide, ethyl Aluminum ethoxy bromide, etc. Examples include alkoxylated and halogenated alkyl aluminum. Examples of the organoaluminum compound belonging to (ii) above include LiAl (C ₂ H ₅ ) ₄ and LiAl (C ₇ H ₁₅ ).
_{4 and the} like. Further, as the organoaluminum compound similar to (i), an organoaluminum compound in which two or more aluminum atoms are bonded via an oxygen atom or a nitrogen atom can also be used. Examples of such compounds include (C ₂ H ₅ ) ₂ AlOAl (C ₂ H ₅ ) ₂ and (C ₄ H ₉ ) ₂ AlOAl.
(C ₄ H _{9) 2,} can be exemplified _{(C 2 H 5) 2 AlN} (C 2 H 5) Al (C 2 H 5) 2 and the like. Among these, trialkylaluminum is preferable.

The amount of the organoaluminum compound used during steady operation is not particularly limited, but when it is used, it is usually preferably in the range of 0.05 to 1000 mol per mol of the titanium compound.

Although the method of the present invention can be applied to the polymerization of all olefins, it is particularly suitable for α-C 2-12 carbons.
Suitable in the case of olefins, for example ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 4
Homopolymerization of α-olefins such as -methyl-1-pentene and 1-octene, and ethylene and propylene, ethylene and 1-butene, ethylene and 1-pentene, ethylene and 1-hexene, ethylene and 4-methyl-1- Ethene such as pentene, ethylene and 1-octene and carbon number 3 ~
Copolymerization of 12 with α-olefin, copolymerization of propylene with 1-butene, and ethylene with two or more other α
-Suitable for copolymerization with olefins. Also,
It is also preferably used for copolymerization with a diene for the purpose of modifying a polyolefin. Examples of the diene compound used at this time include butadiene, 1,4-hexadiene, ethylidene norbornene and dicyclopentadiene. The comonomer content at the time of polymerization can be arbitrarily selected. For example, in the case of copolymerization of ethylene with an α-olefin having 3 to 12 carbon atoms, in the ethylene / α-olefin copolymer, The α-olefin content of 0 to 40 mol%, preferably 0 to 30
Mol%.

Among the polymerization conditions, the polymerization temperature is 0 to 3
It can be selected from the range of 00 ° C. In slurry polymerization or gas phase polymerization, polymerization is carried out at a temperature lower than the melting point of the produced polymer. The polymerization pressure can be selected from the range of atmospheric pressure to about 100 kg / cm ² .

In order to polymerize the olefin by the method of the present invention, any of slurry polymerization, solution polymerization and gas phase polymerization can be used. Particularly when applied to slurry polymerization or gas phase polymerization, a high effect can be obtained. That is, in a state where oxygen, water, etc. are substantially turned off, from hexane, heptane and other aliphatic hydrocarbons, benzene, toluene, xylene and other aromatic hydrocarbons, cyclohexane, methylcyclohexane and other alicyclic hydrocarbons, etc. Polymerization of the olefin is carried out in the presence or absence of a selected inert hydrocarbon solvent. The reaction phase in the case of slurry polymerization is the liquid phase of the solvent,
In gas phase polymerization, the reaction phase is the gas phase. In the present invention, the hydrogen concentration in these reaction phases is changed at three or more stages within the average residence time at a time interval of less than 1/2 of the average residence time in the polymerization vessel, while the transition metal catalyst such as solid transition is used. The olefin is continuously polymerized by using the metal catalyst component and the organometallic compound as a catalyst.

The method for changing the hydrogen concentration in the reaction phase is not particularly limited. In the case of slurry polymerization, a solvent in which a fixed amount of hydrogen is dissolved may be supplied to the polymerization vessel to change the hydrogen concentration in the solvent. However, usually in both cases of slurry polymerization and gas phase polymerization, a system that directly supplies hydrogen into the polymerization vessel is adopted, and the hydrogen gas supply amount fed into the same polymerization vessel is determined by the average retention in the polymerization vessel. It is convenient to use a method of continuously polymerizing an olefin by using a solid transition metal catalyst component and an organometallic compound as a catalyst at a time interval of less than 1/2 of the time, while changing three or more steps within the average residence time. Yes preferred. There is no particular limitation on the method of changing the amount of hydrogen supplied to the polymerization vessel. An appropriate hydrogen supply method can be used.

The hydrogen concentration can be changed continuously or discontinuously and is not particularly limited. The changing time interval is less than 1/2 of the average residence time in the subject polymerization vessel, but is preferably 1/5 or less. If the time interval is too short, there is also a delay in response time, and the effect of change is unlikely to occur. Therefore, it is usually 1/50 or more of the average residence time. Within the above range, the time intervals may be the same or different. Although it depends on the reactor volume, the reaction substrate flow rate, etc., the average residence time in a generally industrial slurry polymerization vessel is in the range of several tens of minutes to several tens of hours. The same applies to the case of gas phase polymerization. If the average residence time is longer to some extent, the effect is more likely to be exhibited when the hydrogen supply amount is changed. Therefore, it is usually preferable to carry out the present invention using a polymerization vessel having an average residence time of 30 minutes or more. The hydrogen supply amount is changed in three or more stages within the average residence time. In the case of two stages, it is difficult to obtain the effect in the case of continuous polymerization, which is not preferable.

The mode of changing the amount of hydrogen supply is preferably changed discontinuously rather than continuously because the effect of broadening the molecular weight distribution can be easily obtained. FIG. 1 is a schematic diagram showing the relationship between the hydrogen supply amount and the polymerization time in the example of the present invention. Specifically, as shown in the figure, the hydrogen supply amount is changed in a rectangular shape. In this case, the minimum value of the hydrogen supply amount can be set to zero. However, if the hydrogen supply amount is made completely zero, the molecular weight of the produced polyolefin may become too high. Therefore, it is usually preferable not to make the minimum value of the hydrogen supply amount zero but to flow a fixed amount. In order to do so, for example, two hydrogen supply lines are provided in the polymerization vessel, a certain amount of hydrogen is constantly supplied to one line, and the hydrogen supply amount of the other line is adjusted by an appropriate control valve. Any method can be used. The above aspect can also be achieved by providing an appropriate adjusting valve on one supply line or a plurality of supply lines. As shown in FIG. 1, when the hydrogen supply amount is changed in a rectangular shape and at least a constant amount of hydrogen is introduced, the ratio of the low supply amount to the high supply amount is 0.1 to 0.9. And preferably in the range of 0.1 to 0.8.

When the amount of hydrogen supplied to the same polymerization vessel is changed in a rectangular manner as described above, it takes a certain period of time after the amount of hydrogen supply is changed until the molecular weight of the produced polymer actually changes. Delays may occur. As a countermeasure against this, for example, when the hydrogen supply amount is increased, hydrogen is supplied at a supply amount about 1 to 200% higher than a predetermined high supply amount for about 1 to 50% of a predetermined supply time, and then a predetermined amount is supplied. The hydrogen supply is switched to a high supply amount and supply time. On the contrary, when the hydrogen supply amount is reduced, hydrogen is supplied at a supply amount of about 1 to 100% lower than the predetermined low supply amount, and then the hydrogen is supplied at a predetermined low level for about 1 to 50%. Switch to hydrogen supply according to supply amount and supply time. By such a method, it is possible to eliminate the delay in the effect corresponding to the change in the hydrogen supply amount. FIG. 2 is a schematic diagram showing the relationship between the hydrogen supply amount and the polymerization time in the example using the above method.

In the present invention, it is necessary to change the hydrogen concentration in the reaction phase or the hydrogen supply amount, but other polymerization conditions such as polymerization temperature, catalyst supply amount, olefin supply amount such as ethylene, 1- It is also possible to appropriately change the supply amount of a comonomer such as butene, the supply amount of a solvent in slurry polymerization, or the like simultaneously with or separately from the change of hydrogen.

The present invention is not limited to the method shown in the examples below,
It can be implemented in various ways. In addition to the case where polyolefin is continuously produced with only one polymerization vessel,
In the continuous production method of polyolefin using a plurality of polymerization vessels in series or in parallel, or in combination thereof, the method of the present invention can be applied to any one or a plurality of polymerization vessels. When a plurality of polymerizers are used, the same or different slurry polymerization, gas phase polymerization or solution polymerization can be adopted for each polymerization reactor.

The polyolefin produced by the method of the present invention is pelletized by mechanical melt mixing using a pelletizer, a homogenizer or the like according to a conventional method, and then molded by various molding machines to obtain a desired molded product. Further, the polyolefin obtained by the method of the present invention, in addition to other olefin-based polymers and rubber, in accordance with a conventional method, an antioxidant, an ultraviolet absorber, a light stabilizer, a lubricant, an antistatic agent, an antifogging agent, Known additives such as anti-blocking agents, processing aids, color pigments, cross-linking agents, foaming agents, inorganic or organic fillers, flame retardants and the like can be added.

[0052]

BEST MODE FOR CARRYING OUT THE INVENTION The amount of hydrogen gas fed into the same polymerization vessel is changed at three or more stages within the average residence time at a time interval of less than 1/2 of the average residence time in the polymerization vessel. The transition metal catalyst component [A] and the organometallic compound (B-
Using an olefin polymerization catalyst comprising 1) and at least one compound [B] selected from the group consisting of compounds (B-2) which react with the transition metal catalyst component [A] to form an ion pair By continuously polymerizing the olefin, it is possible to produce a polyolefin having a wide molecular weight distribution and an excellent balance of various physical properties such as flow properties and mechanical properties.

[0053]

EXAMPLES The present invention will now be described in detail with reference to Examples. First, the test method used in the present invention will be described. (1) Density Density gradient tube method (23
℃). (2) N-value Using a Koka type flow tester (manufactured by Shimadzu Corporation), extruding from a die of 2 mmφ × 40 mm at a resin temperature of 170 ° C.,
Low test pressure 20kg / cm ² and high test pressure 150kg / c
The apparent shear rate in m ² is calculated and calculated by the following formula [IV].

[Equation 1] (3) Melt flow rate (MFR) Measured according to JIS K6760. (Measurement temperature 190 ° C, load 2.16 kg) (4) Tensile yield strength (YTS) According to JIS K6760. (Pulling speed 50mm / mi
n, test piece thickness 2 mm) (5) Tensile impact value (TIS) Measured in accordance with ASTM D1822. (Test piece thickness 1.
5 mm) (6) Bending stiffness Measured according to JIS K7106. (Toyo Seiki
(A bending stiffness tester manufactured by Co., Ltd. is used) (7) Melt tension (MT) Measured by a melt tension tester manufactured by Toyo Seiki Co., Ltd. (Measurement temperature 190 ° C.) (8) Critical shear rate (γ _c ) Measured with a capillary rheometer manufactured by INTESCO Corporation. (Measurement temperature 190 ℃) (9) Environmental stress crack resistance (ESCR) F of constant strain ESCR according to JIS K6760
_Find the value of ₅₀ . (10) Die swell ratio (DSR) Using a high-performance flow tester, a sample is extruded at a temperature of 170 ° C., and the ratio between the strand diameter and the die inner diameter is determined.
The shear rate is measured at an extrusion rate corresponding to 80 sec ^-1 .

<Catalyst Production Example> As the solid catalyst component, a Ti-based catalyst prepared by the dissolution precipitation method was used. The manufacturing method is as follows. After thoroughly replacing the inside of a 3-liter flask with a capacity of 1 liter equipped with a stirrer and a cooler with nitrogen, 250 ml of dry hexane and 11.4 g of anhydrous magnesium chloride and n which had been pulverized in advance with a 3-liter vibration mill for 1 hour. -Add 110 ml of butanol,
It heated at 68 degreeC for 2 hours, and it was set as the uniform solution (A). After cooling this solution (A) to room temperature, the kinematic viscosity at 25 ° C was 2
8 g of methyl hydrogen polysiloxane which is 5 cSt
Was added and stirred for 1 hour to obtain a uniform solution (B). After cooling the solution (B) with water, titanium tetrachloride 50
ml and dry hexane 50 ml using a dropping funnel 1
The solution was added dropwise over a period of time to obtain a solution (C). Solution (C)
Was homogeneous, and the complex of the reaction product was not precipitated. While refluxing the solution (C), heat treatment was performed at 68 ° C. for 2 hours. Precipitation of the reaction product complex (D) was observed about 30 minutes after the heating was started. This was collected, washed 6 times with 250 ml of dry hexane, and further dried with nitrogen gas to recover 19 g of the reaction product complex (D). When the reaction product complex (D) was analyzed, Mg 14.5 wt%, n-
It contained butanol 44.9 wt% and Ti 0.3 wt%, and its specific surface area was 17 m ² / g. When the reaction product complex (D) was observed with a scanning electron microscope (SEM), it had a shape close to a sphere. Reaction product complex (D)
In a nitrogen atmosphere, 4.5 g was collected in a 1-liter three-necked flask equipped with a stirrer and a condenser, 250 ml of dry hexane and 25 ml of titanium tetrachloride were added, and the mixture was heated under reflux at 68 ° C. for 2 hours. After cooling to room temperature, wash 6 times with 250 ml of dry hexane,
After drying with nitrogen gas, 4.6 g of the solid catalyst component (E) was recovered. Analysis of this solid catalyst component (E) revealed that Mg
12.5 wt%, n-butanol 17.0 wt% and Ti 9.
It contained 0 wt% and its specific surface area was 29 m ² / g. When the solid catalyst component (E) was observed by SEM, the particle diameter was uniform and the shape was close to a sphere.

<Examples 1 and 2> FIG. 3 (a) is a schematic process diagram of the slurry method one-stage polymerization process used.
In the figure, a stirred reactor having an internal volume of 70 liters is used as the reactor 1, the solid catalyst component (E) obtained in the above catalyst production example is supplied from the catalyst supply line 2, and triethylaluminum (TEA) is used as a cocatalyst. Was fed from the organometallic compound feed line 3 to continuously polymerize ethylene with 1-butene under the polymerization conditions shown in Table 1. In the figure, reference numeral 4 is an ethylene supply line, 5 is a comonomer supply line, 6 is a hydrogen supply line (6a is a continuous hydrogen supply line, and 6b is an intermittent hydrogen supply line) and 7
Indicates a polymerization solvent supply line. Hydrogen is supplied in Table 1 using the continuous hydrogen supply line 6a and the intermittent hydrogen supply line 6b.
Supply was carried out under the conditions shown in. The intermittent hydrogen supply device is a mass flow meter (EP-TF).
-5310), controller (EP-TC-100
0) and converter unit (TM-7420-23)
A thermal mass flow meter manufactured by Tokyo Keiso Co., Ltd., which is comprised of 1) was used. The slurry polymerization product produced in the reactor 1 is introduced into the flushing tank 9 through the polymerization product transfer line 8, the polymerization product is continuously extracted from the polymerization product recovery line 10, and the unreacted gas is extracted from the degassing line 11. Was removed. After granulating the obtained polymer particles with a pelletizer, a test piece or film is molded by injection molding or inflation molding,
The physical properties were evaluated. The results are shown in Table 1.

<Comparative Example 1> Using the same process as in Examples 1 and 2, one-stage polymerization was carried out by an ordinary method, that is, a method without intermittent hydrogen supply. Table 1 shows the polymerization conditions and the results of physical property evaluation of the polymer. From the above results, a wide molecular weight distribution polyolefin obtained by the method of the present invention and a polyolefin composition containing the same,
It can be seen that the melt elasticity represented by the melt tension and the die swell ratio and the flow characteristics represented by the critical shear rate are remarkably improved, and the mechanical properties are well balanced in various physical properties.

<Example 3> In the same process as in Examples 1 and 2, only intermittent supply was used as the hydrogen supply method. FIG. 3B is a schematic system diagram of intermittent hydrogen supply used in Example 3. That is, hydrogen intermittent supply lines 6b1, 6b2 and 6 in which three hydrogen intermittent supply devices are arranged in parallel are arranged.
Using b3, one-stage slurry polymerization was continuously carried out under the polymerization conditions shown in Table 1. The hydrogen supply cycle in each intermittent hydrogen supply line is as follows. (1) Supply at 6b1: 40Nl / hr for 9 minutes and then stop for 1 minute. (2) 200 minutes after 4 minutes from the start of 6b2: 6b1
After feeding for 1 minute at Nl / hr, stop for 9 minutes. (3) 6b3: 5 minutes after the start of supply by 6b1, 120
After feeding for 4 minutes at Nl / hr, stop for 6 minutes. The total amount of hydrogen supplied to the polymerization vessel was 40 Nl / hr for 4 minutes, 240 Nl / hr for 1 minute, 160 in total as the above lines.
This means that a cycle consisting of Nl / hr for 4 minutes and supply stop for 1 minute was continuously repeated. In this way, the supply amount is set to 0 before the predetermined low hydrogen amount (40 Nl / hr) is supplied, and the higher supply amount (240 Nl / hr) is set before the predetermined high hydrogen amount (160 Nl / hr) is supplied. As a result, it was possible to eliminate the delay in the effect corresponding to the change in the hydrogen supply amount. The results of physical property evaluation of the obtained polymer are shown in Table 1.
Shown in

[0058]

[Table 1]

[0059]

INDUSTRIAL APPLICABILITY The polyolefin having a wide molecular weight distribution according to the present invention has a small block composed of polyolefins having different molecular weights, so that the dispersed state thereof in the polymer particles is uniform, and as a result, a polyolefin composition containing them is , Has the following features. (1) Particularly excellent in melt elasticity such as melt tension and die swell ratio. (2) Excellent mechanical properties such as tensile impact value, bending stiffness, and environmental stress crack resistance. (3) Since it has excellent flow characteristics such as critical shear rate, it has good moldability in high-speed molding and the like. (4) Generation of high molecular weight gel and fish eyes is extremely small, and excellent homogeneity is obtained. According to the present invention, it is possible to easily and easily produce a polyolefin composition that is homogeneous and has an excellent balance of various physical properties. The polyolefin having a wide molecular weight distribution obtained by the present invention and the polyolefin composition containing the same can be used for various films, sheets, pipes, hollow containers, various coating materials, foaming materials, etc. due to the advantages described above. it can. Also, extrusion molding,
Since it can be suitably used for all molding methods such as blow molding and injection molding, a wide range of molded products can be obtained. According to the first and third inventions of the present application, it is possible to produce a polyolefin having good dispersibility of a high molecular weight component. According to the second and fourth inventions of the present application, the hydrogen concentration in the reaction phase can be easily changed. Further, according to the fifth invention of the present application, the effect due to the change of the hydrogen concentration can be remarkably exhibited.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an example of a relationship between a hydrogen supply amount and a polymerization time.

FIG. 2 is a schematic diagram showing another example of the relationship between the hydrogen supply amount and the polymerization time.

FIG. 3A is a schematic process diagram of an example of a one-stage polymerization process of the present invention, and FIG. 3B is a schematic system diagram of an intermittent hydrogen supply method of another example.

[Explanation of symbols] 1 reactor 2 catalyst supply line 3 organometallic compound supply line 4 ethylene supply line 5 comonomer supply line 6 hydrogen supply line 6a hydrogen continuous supply line 6b, 6b1, 6b2, 6b3 intermittent hydrogen supply line 7 polymerization solvent supply Line 8 Polymerization product transfer line 9 Flushing tank 10 Polymerization product recovery line 11 Degassing line

Claims (5)

[Claims] 1. A transition metal while changing the hydrogen concentration in the reaction phase in the same polymerization vessel in three or more steps within the average residence time at a time interval of less than 1/2 of the average residence time in the polymerization vessel. The catalyst component [A] and the organometallic compound (B-
1) and at least one compound [B] selected from the group consisting of the compound (B-2) which reacts with the transition metal catalyst component [A] to form an ion pair. A method for producing a polyolefin having a wide molecular weight distribution, characterized by polymerizing an olefin. 2. The supply amount of hydrogen gas fed into the same polymerization vessel is changed at three or more stages within the average residence time at a time interval of less than 1/2 of the average residence time in the polymerization vessel, The transition metal catalyst component [A] and the organometallic compound (B-
1) and at least one compound [B] selected from the group consisting of the compound (B-2) which reacts with the transition metal catalyst component [A] to form an ion pair. A method for producing a polyolefin having a wide molecular weight distribution, characterized by polymerizing an olefin. 3. A solid transition while changing the hydrogen concentration in the reaction phase in the same polymerization reactor at three or more stages within the average residence time at a time interval of less than 1/2 of the average residence time in the polymerization reactor. A method for producing a polyolefin having a wide molecular weight distribution, which comprises continuously polymerizing an olefin using a metal catalyst component and an organometallic compound as a catalyst. 4. The supply amount of hydrogen gas fed into the same polymerization vessel is changed at three or more stages within the average residence time at a time interval of less than 1/2 of the average residence time in the polymerization vessel, A method for producing a polyolefin having a wide molecular weight distribution, which comprises continuously polymerizing an olefin using a solid transition metal catalyst component and an organometallic compound as a catalyst. 5. The method according to claim 1, wherein the hydrogen concentration or the hydrogen gas supply amount is changed discontinuously.
5. A method for producing a polyolefin having a wide molecular weight distribution according to any one of 1.