JP3223569B2 - Method for producing polyolefin - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a polyolefin. More specifically, the present invention is a method for producing a polyolefin capable of arbitrarily controlling the molecular weight distribution with excellent polymerization activity.Furthermore, the polymer has good particle shape and excellent powder properties, The present invention relates to a method for producing a polyolefin capable of obtaining a copolymer having good transparency and excellent melt properties such as melt tension in polymerization.

[0002]

2. Description of the Related Art It is already known to use a catalyst system comprising a combination of a transition metal compound and an organometallic compound as a method for producing a polyolefin by polymerization of an olefin. More recently, a method for producing a polyolefin in the presence of a catalyst component comprising a solid catalyst component containing an organometallic compound and a solid catalyst component containing magnesium, titanium, and halogen as main components, for example, using magnesium chloride and titanium tetrachloride as a highly active catalyst has been proposed. Many have been proposed. However, in a catalyst system containing a titanium compound as a main component, there is a limit in controlling the molecular weight distribution of a produced polymer, and a catalyst capable of arbitrarily controlling the molecular weight distribution in accordance with diversification of polyolefin quality is demanded.

For this reason, Japanese Patent Publication No. 52-39714 has already been published.
In the above item, high activity is obtained by using a catalyst system comprising a reaction product of a metal magnesium, an organic compound of a hydroxide, an organic oxygen compound of a transition metal, a halogen-containing compound of a transition metal and an aluminum halide, and an organometallic compound. A polymerization method capable of producing a polyolefin having an arbitrary molecular weight distribution while maintaining the same has been proposed. In this proposal, the use of magnesium metal, which is relatively easy to handle compared to magnesium chloride and titanium tetrachloride, a hydroxylated organic compound such as alcohol, and a transition metal organic oxygen compound such as titanium tetrabutoxide, requires preparation of a catalyst component. Discloses a method for preparing a catalyst which has many industrial advantages without problems of controlling moisture and corrosion of preparation equipment. However, the polymerization activity of the catalyst system according to this proposal is not yet sufficient, and there is room for improvement. Further, when an ethylene / α-olefin copolymer is produced using the catalyst system according to this proposal, the composition distribution is wide, and α-olefin units incorporated in the polymer are present in a large amount on the low molecular weight side. And inferior transparency.

Further, the polymer particles obtained in the presence of these catalyst systems have a small average particle size or a wide particle size distribution, so that the proportion of fine particles contained in the polymer particles is large, They were still inadequate in terms of body characteristics.

[0005]

Therefore, it is possible to control a wide range of molecular weight distribution, to produce a polymer having excellent particle shape with high activity, and to provide a copolymer having a narrow composition distribution in copolymerization. The development of a catalyst system is desired.

[0006]

Means for Solving the Problems Accordingly, the present inventors have:
Catalysts that use metal magnesium, organic hydroxides such as alcohols, and transition metal organic oxygen compounds such as titanium tetrabutoxide, which have many industrial advantages without the problem of moisture control and corrosion of the preparation equipment in the preparation of catalyst components As a result of further intensive studies on the production method, they have found a surprising catalyst system that can control the molecular weight distribution with very high activity and can also control the composition distribution during copolymerization, and completed the present invention. It led to.

That is, according to the present invention, when producing a polyolefin in the presence of a catalyst comprising a transition metal compound and an organometallic compound, (A) as components (i) magnesium metal and a hydroxide organic compound, and oxygen-containing organic compound of magnesium At least one member selected from compounds, and (ii) a compound represented by the general formula [Me ¹ O _a (OR ¹ ) _b X ¹ _c ] _m (the general formula
In the formula, Me ¹ is a transition metal of Group IVa of the periodic table.
Ri, R ¹ represents a hydrocarbon group having 1 to 20 carbon atoms, X ¹ is
A represents a halogen atom, and a, b and c represent a> 0 and b>
0, 4> c ≧ 0 and compatible with the valence of the transition metal
And m represents an integer. The homogeneous solution containing an oxygen-containing organic compound of at least one transition metal represented by), (iii) the general formula (cyclopentadienyl compound) _p Me ² L
_qp (In the formula, Me ² represents a transition metal of Group IVa of the periodic table.
And L is less than or equal to cyclopentadienyls coordinating to the transition metal.
Represents an outer ligand. p is the coordination of cyclopentadienyls
An integer representing a number, q represents the valence of the transition metal. p, q
Is in the range of 1 ≦ p ≦ q, and 2 when p is p ≧ 2,
Ligands of cyclopentadienyls are silylene groups,
Substituted silylene group, alkylene group, substituted alkylene group, sulfur
Two or more may be bonded via yellow. )
At least one kind of a cyclopentadienyl compound of a transition metal compound having a ligand was added and then, (iv) at least one kind of halogenated organic aluminum compound and (v) at least one or more organic aluminum that (C) polymerizing at least one or more α-olefins in the presence of a solid catalyst obtained by adding an oxy compound and a catalyst system comprising an organic aluminum compound and / or an organic aluminum oxy compound as a component (B). Is a method for producing a polyolefin.

[0008]

In the present invention, the following are mentioned as the reactant used in the preparation of the solid catalyst component (A) (i) of the metal magnesium and the organic hydroxide compound and the oxygen-containing organic compound of magnesium. First, when using metal magnesium and a hydroxylated organic compound,
Various forms of metallic magnesium, namely powder,
Any shape such as particles, foils or ribbons can be used. As the hydroxylated organic compound, alcohols,
Organic silanols and phenols are suitable.

As the alcohol, a linear or branched aliphatic alcohol having 1 to 18 carbon atoms, an alicyclic alcohol or an aromatic alcohol can be used. Examples are methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol, n-hexanol, 2-ethylhexanol, n-
Octanol, i-octanol, n-stearyl alcohol, cyclopentanol, cyclohexanol, ethylene glycol and the like can be mentioned.

The organic silanol has at least one hydroxyl group, and the organic group has 1 to 12 hydroxyl groups.
Alkyl groups, preferably having 1 to 6 carbon atoms, cycloalkyl groups, arylalkyl groups,
It is selected from an aryl group, an alkylaryl group and an aromatic group. For example, trimethylsilanol, triethylsilanol, triphenylsilanol, t-butyldimethylsilanol and the like can be mentioned.

Further, phenols include phenol, cresol, xylenol, hydroquinone and the like.

These hydroxylated organic compounds are used alone or as a mixture of two or more. It is of course good to use it alone, but if it is used as a mixture of two or more types, it may bring out a specific effect on the powder properties of the polymer.

In addition, when the solid catalyst component described in the present invention is obtained using metallic magnesium, a substance which reacts with metallic magnesium or forms an addition compound, for example, for the purpose of accelerating the reaction, for example, Iodine, chloride second
It is preferable to add one or more polar substances such as mercury, alkyl halides, organic acid esters and organic acids.

The compounds belonging to the oxygen-containing organic compounds of magnesium include magnesium alkoxides, for example, methylate, ethylate, isopropylate, decanolate, methoxyethylate and cyclohexanolate, magnesium alkyl alkoxides,
For example, ethyl ethylate, magnesium hydroalkoxides such as hydroxymethylate, magnesium phenoxides such as phenate, naphthenate, phenanthrate and cresolate, magnesium carboxylates such as acetate, stearate, benzoate, phenylacetate, adipate, sebacate Phthalates, acrylates and oleates, oximates such as butyloximate, dimethylglyoximate and cyclohexyloximate, hydroxamic salts, hydroxylamine salts such as N
-Etroso-N-phenyl-hydroxylamine derivatives, enolates such as acetylacetonate, magnesium silanolates such as triphenylsilanolate, complex alkoxides of magnesium with other metals,
An example is Mg [Al (OC ₂ H ₅ ) ₄ ] ₂ .
These oxygen-containing organomagnesium compounds are used alone or as a mixture of two or more.

As the oxygen-containing organic compound of the transition metal as the reactant (ii), the general formula [Me ¹ O _a (O
The compound represented by R ¹ ) _b X ¹ _c ] _m is used. However, Me ¹ in said general formula is a IV a group transition metal of the Periodic Table, e.g., titanium, zirconium, and <br/> Hafuniu beam is Agerare, particularly titanium, zirconium is preferred. R ¹ represents a hydrocarbon group such as C 1-20, preferably a linear or branched chain alkyl group having from 1 to 10, a cycloalkyl group, an arylalkyl group, an aryl group and an alkylaryl group having a carbon, X ¹ is a halogen atom And is fluorine, chlorine, bromine or iodine. a, b
And c are a ≧ 0, b> 0, and 4> c ≧ 0, and represent numbers compatible with the valence of the transition metal, and m represents an integer. In particular, it is desirable to use an oxygen-containing organic compound in which a is 0 ≦ a ≦ 1 and m is 1 ≦ m ≦ 6.

As specific examples, tetraethoxytitanium, tetrapropoxytitanium, tetraisopropoxytitanium, tetrabutoxytitanium, Ti ₂ O (OiC ₃
H ₇ ) _{6 and the} like. A transition metal compound obtained by replacing the transition metal in these titanium compounds with zirconium can also be used. The use of oxygen-containing organic compounds having several different hydrocarbon groups also falls within the scope of the present invention. These oxygen-containing organic compounds of transition metals are used alone or as a mixture of two or more.

In the present invention, a silicon compound can be used for the purpose of improving the shape of the polymer. Specifically, the following polysiloxanes and silanes are used. Examples include chain polysiloxanes such as dimethylpolysiloxane and methylhydropolysiloxane, and alkoxysilanes such as methyltrimethoxysilane, tetramethoxysilane, and tetraethoxysilane.

The above-mentioned organosilicon compounds may be used alone or in combination of two or more.

The transition metal compound having cyclopentadienyls as a ligand as the reactant (iii) includes:
General formula, (cyclopentadienyls) _p Me ² L _qp (where Me ² represents a transition metal of Group IVa of the periodic table ;
Is a ligand other than cyclopentadienyls that coordinates to the transition metal, and represents, for example, a hydrocarbon group, an alkoxy group, halogen or hydrogen. P is an integer representing the coordination number of cyclopentadienyl, and t represents the valence of the transition metal.
p and q are in the range of 1 ≦ p ≦ q, and when p is p ≧ 2, the ligand of two cyclopentadienyls is a silylene group, a substituted silylene group, an alkylene group, a substituted alkylene. Two or more groups may be bonded via a group or sulfur. ).

In the above general formula, the same transition metal as that of Me ¹ can be used. Specifically, zirconium is preferably hafnium or titanium down.

The ligand of cyclopentadienyl includes, for example, cyclopentadienyl group, indenyl group, fluorenyl group and the like.

Examples of ligands other than cyclopentadienyls include, for example, hydrocarbon groups such as methyl group, ethyl group and propyl group, and alkoxy groups such as methoxy group and ethoxy group. Examples of the halogen include fluorine, chlorine, bromine, and iodine.

Specific examples of the transition metal compound having a cyclopentadienyl as a ligand include bis (cyclopentadienyl) zirconium dichloride, bis (cyclopentadienyl) zirconium monochloride monohydride, and the like. Bis (cyclopentadienyl) methylzirconium hydride, bis (cyclopentadienyl) zirconium methoxychloride, bis (indenyl) zirconium dichloride, bis (fluorenyl) zirconium dichloride, ethylenebis (indenyl) zirconium dichloride, dimethylsilylenebis (cyclopentane Dienyl) zirconium dichloride, thiobis (cyclopentadienyl) zirconium dichloride, and the like. It is also possible to use a transition metal in these zirconium compounds, titanium or placed Hafuniu beam conversion <br/> example transition metal compound.

The organoaluminum halide compound as the reactant (iv) includes a compound represented by the general formula R ² _z Al ¹ X
^The one indicated by _23-z is used. Here, in the general formula, R ² represents a hydrocarbon group having 1 to 20, preferably 1 to 8 carbon atoms, X represents a halogen atom, and z is a number of 0 <z <3, preferably 0 <z ≦ 2
Represents the number of Further, R ² is preferably selected from a linear or branched alkyl group, a cycloalkyl group, an arylalkyl group, an aryl group and an alkylaryl group.

Specific examples of the organoaluminum halide compound include, for example, dimethylaluminum chloride, diethylaluminum chloride, diethylaluminum bromide, dipropylaluminum chloride, ethylaluminum dichloride, i-butylaluminum dichloride, methylaluminum sesquichloride, ethylaluminum Sesquichloride, i-butylaluminum sesquichloride, a mixture of triethylaluminum and aluminum trichloride, and the like.

The above organoaluminum halide compounds can be used alone or as a mixture of two or more.

As the organoaluminum oxy compound as the reactant (v), conventionally known aluminoxane can be used. For example, methylaluminoxane, ethylaluminoxane, propylaluminoxane and the like can be mentioned. As this aluminoxane, for example, aluminoxane which is a reaction product of an organic aluminum compound such as trimethylaluminum, diisobutylaluminum hydride, ethylaluminum sesquichloride and water is usually used.

The order of using the reactants (iv) and (v) is not particularly limited. That is, (i)
The organoaluminum halide compound as the reactant v) and the organoaluminum oxy compound as the reactant (v) may be used separately or as a mixture.
Preferably, after reacting the organoaluminum halide compound, it is desirable to add the organoaluminum oxy compound.

These reactions are preferably performed in a liquid medium. Therefore, especially when these reactants themselves are not liquid under the operating conditions, or when the amount of the liquid reactants is insufficient, the reaction should be carried out in the presence of an inert organic solvent. As the inert organic solvent, any of those generally used in the art can be used, and examples thereof include aliphatic, alicyclic or aromatic hydrocarbons or their halogen derivatives or mixtures thereof, for example, isobutane, Hexane, heptane, cyclohexane, benzene, toluene, xylene, monochlorobenzene and the like are preferably used.

The amount of the reactant used in the present invention is not particularly limited.
Is the atomic ratio of the gram atom of the transition metal (Me ¹ ) in the transition metal compound of (ii) to 1/20 ≦
Mg / Me ¹ ≦ 100, preferably 1/5 ≦ Mg / M
e ¹ ≦ 10. When Mg / Me ¹ is too large out of this range, it becomes difficult to obtain a homogeneous solution containing Mg and transition metal in the catalyst preparation, the activity of the catalyst decreases during the polymerization. Conversely, if it is too small, the activity of the catalyst will be low, causing problems such as coloring of the product.
Thus, a homogeneous solution containing Mg and a transition metal can be obtained from the reactants (i) and (ii).

The gram atom of the transition metal (Me ² ) having the above-mentioned (iii) cyclopentadienyl as a ligand and the gram atom of the transition metal (Me ¹ ) in the transition metal compound of the above (ii). The atomic ratio is important in controlling the molecular weight distribution of the polyolefin, and is 1/100 ≦ Me ² / Me ¹
It is preferred to use an amount such that ≦ 10, especially 1/20 ≦ Me ² / Me ¹ ≦ 5.

In the present invention, the type and amount of the organoaluminum halide (iv) must also be appropriately selected. That is, the catalytic properties of the active species generated from the transition metal oxygen-containing organic compound (ii) and the transition metal cyclopentadienyl compound (iii) as a ligand are determined by the type of organoaluminum halide and Control by quantity. More specifically, the gram atom of Mg in the magnesium compound of (i) and the (i)
v) The atomic ratio of aluminum (Al ¹ ) to the gram atom in the organoaluminum halide is 1/20 ≦ Mg
/ Al ¹ ≦ 10, preferably 1/5 ≦ Mg / Al ¹ ≦
5

The gram atom of aluminum (Al ² ) in the organoaluminum oxy compound of (v) and the (i)
ii) The transition metal (Me ² ) having a cyclopentadienyl compound as a ligand has an atomic ratio of 1 ≦ Al ² / M to a gram atom.
e ² ≦ 1000, preferably 10 ≦ Al ² / Me ² ≦
200.

The reaction conditions at each stage are not particularly limited, but at a temperature in the range of -50 to 300 ° C, preferably 0 to 200 ° C, for 0.5 to 50 hours, preferably 1 to 6 hours. It is carried out at normal pressure or under pressure in a gas atmosphere.

The solid catalyst component (A) thus obtained can be subjected to polymerization as it is in a suspended state. In some cases, the solid catalyst component (A) may be separated from a solvent, and further, may be heated under normal pressure or reduced pressure. It can also be used in a dried state after removing the solvent.

In the present invention, the catalyst component (B) includes an organic aluminum compound and / or an organic aluminum oxy compound comprising an aluminum metal and an organic group. Examples of the organic group include an alkyl group. As the alkyl group, a linear or branched alkyl group having 1 to 20 carbon atoms is used. Specifically, for example, trimethylaluminum, triethylaluminum, tri-i-butylaluminum,
Tri-n-butylaluminum and tri-n-decylaluminum are exemplified. In particular, it is preferable to use a trialkylaluminum having a linear or branched alkyl group having 1 to 10 carbon atoms.

As the organoaluminum compound, an alkyl metal hydride having an alkyl group having 1 to 20 carbon atoms can be used. Specific examples of such compounds include diisobutylaluminum hydride. Further, an alkyl aluminum halide having an alkyl group having 1 to 20 carbon atoms, for example, ethyl aluminum sesquichloride, diethyl aluminum chloride, diisobutyl aluminum chloride or an alkyl aluminum alkoxide, for example, diethyl aluminum ethoxide, can also be used.

An organoaluminum compound obtained by reacting a hydride of a trialkylaluminum or dialkylaluminum having an alkyl group having 1 to 20 carbon atoms with a diolefin having 4 to 20 carbon atoms, for example, a compound such as isoprenyl aluminum Can also be used.

The above-mentioned organoaluminum compounds may be used alone or in combination of two or more.

Further, as the organoaluminum oxy compound, those similar to the above (v) can be used.

The polymerization of the olefin according to the present invention can be carried out in a liquid phase or a gas phase, and can be carried out under general reaction conditions of the so-called Ziegler method. That is, polymerization is carried out at a temperature of 20 to 250 ° C. in a continuous or batch manner. The polymerization pressure is not particularly limited, but the use of 1.5 to 2500 kg / cm ² G under pressure is particularly suitable. When the polymerization is carried out in the liquid phase, it is carried out in the presence of an inert solvent. As the inert solvent, any commonly used solvent can be used. Particularly suitable are alkanes or cycloalkanes having 4 to 20 carbon atoms, such as, for example, isobutane, pentane, hexane, cyclohexane and the like.

When the polymerization is carried out in the gas phase, it is desirable to carry out prepolymerization with 0.01 to 50 g of ethylene or α-olefin having 3 or more carbon atoms per 1 g of the solid catalyst component (A). The contact condition with the monomer is not particularly limited,
It is necessary to perform in a state where oxygen, water, and the like are substantially free.
Generally, this contact treatment can be carried out at a temperature of -50 to 100 ° C, preferably 0 to 50 ° C, under normal pressure or under pressure. When the treatment is performed in a liquid phase, it is preferable to bring the mixture into sufficient contact under stirring. The monomers used for the prepolymerization can be used alone or in combination of two or more. In the case of prepolymerization of two or more, the prepolymerization can be performed sequentially or simultaneously. In the preliminary polymerization, it is desirable to use the organoaluminum compound in a ratio of 0.1 to 1000 mol per 1 mol of the transition metal atom in the solid catalyst component (A).

In the case of performing gas phase polymerization, a reactor used in the polymerization step may be appropriately selected from those commonly used in the art, such as a fluidized bed type polymerization vessel and a stirred tank type polymerization vessel. When a fluidized bed type polymerization vessel is used, the reaction is carried out while blowing the gaseous olefin and / or an inert gas into the system while keeping the reaction system in a fluidized state. In the case of using a stirred tank type polymerization vessel, various types of stirrers such as an squid type stirrer, a screw type stirrer, and a ribbon type stirrer can be used.

The polymerization of the present invention includes not only homopolymerization of α-olefins but also copolymerization of two or more α-olefins.
As the α-olefin used for the polymerization, ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1
-Octene, 4-methyl-1-pentene and the like. In order to introduce a double bond into the polymer, copolymerization can be carried out using a mixture of an α-olefin and a diene such as butadiene and isoprene. It is necessary to select the amount of the α-olefin used for the copolymerization according to the density of the target polymer. The density of the polymer according to the present invention can be produced in the range of 0.890 to 0.970 g / cm ³ .

The polymerization operation of the present invention can be carried out not only in the usual one-stage polymerization under one polymerization condition but also in the multi-stage polymerization under a plurality of polymerization conditions.

In the practice of the present invention, the amount of the solid catalyst component (A) used may be per liter of solvent or 1 liter of reactor.
It is preferable to use an amount corresponding to 0.001 to 2.5 mmol per transition metal atom, and a higher concentration can be used depending on conditions.

The organoaluminum compound of the catalyst component (B) is used in an amount of 0.02 per liter of the solvent or 1 liter of the reactor.
It is used at a concentration of .about.1000 mmol, preferably 0.2-100 mmol.

In the present invention, the molecular weight of the produced polymer can be adjusted by a known means, that is, a method of allowing an appropriate amount of hydrogen to be present in the reaction system.

[0049]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

In the examples and comparative examples, HL
MI / MI is a high load melt index (HLMI, A
It is the ratio between the STMD-1238 condition F) and the melt index (MI, according to ASTMD-1238 condition E) and is a measure of the molecular weight distribution. If the HLMI / MI value is small, the molecular weight distribution is considered to be narrow.

The activity indicates the amount of polymer produced (g) per gram of the solid catalyst component. The average particle size of the polymer particles is a value obtained by plotting the result of classifying the polymer particles by a sieve on probability log paper and reading the particle size corresponding to a weight integrated value of 50% from an approximated straight line.

The number of ethyl branches was quantified by a Fourier transform infrared spectrophotometer (FT-IR) from a peak derived from a methyl group appearing at around 1378 cm ^-1 .

Example 1 (a) [Preparation of solid catalyst component (A)] In a 1-liter glass flask equipped with a stirrer, 7.0 g (0.288 mol) of metal magnesium powder and 49.0 g (09.0 g) of titanium tetrabutoxide were added. .144 mol) and n-butanol in which 0.35 g of iodine was dissolved.
8 g (0.60 mol) was added at 90 ° C. over 2 hours,
The mixture was further stirred at 140 ° C. for 2 hours under a nitrogen seal while removing generated hydrogen gas. After the temperature was raised to 110 ° C., 18 g (0.086 mol) of tetraethoxysilane was added.
And 13.2 g of tetramethoxysilane (0.086 mo
l) was added, and the mixture was further stirred at 140 ° C for 2 hours. Then, 490 ml of hexane was added to obtain a homogeneous solution containing Mg and a transition metal.

95.2 g of this homogeneous solution (0.1 mg as Mg)
057 mol) into a separately prepared 500 ml glass flask, and then bis (cyclopentadienyl)
4.2 g of zirconium dichloride (0.014mo
After l) was added and dissolved, 127 ml of a hexane solution containing 0.34 mol of i-butylaluminum dichloride was added to the solution, and the mixture was stirred at 70 ° C. for 1 hour. Further, after removing the supernatant and drying under a nitrogen atmosphere, 3.9 g of a solid catalyst component was placed in a 300 ml glass flask, and then 115 ml of toluene and 31.3 g of a toluene solution of methylaluminoxane (31.3 g of aluminum atom) (In terms of 0.091 mol), and the mixture was stirred at 30 ° C. for 1 hour. Thereafter, toluene was removed under reduced pressure using an evaporator. Hexane was added to the product, and the product was washed seven times by a gradient method. Thus, a slurry of the solid catalyst component (A) suspended in hexane was obtained. A part thereof was collected, the supernatant was removed, dried under a nitrogen atmosphere, and subjected to elemental analysis. As a result, it was found that Ti was 3.1% by weight and Zr was 4.0% by weight.

(Ii) [Polymerization] The inside of a stainless steel electromagnetically stirred autoclave having an inner volume of 2 l was sufficiently replaced with nitrogen, 1.2 l of hexane was charged, and the inner temperature was adjusted to 80 ° C. Then, the catalyst component (B)
And a slurry containing 2.3 mg atom of methylaluminoxane in terms of aluminum atom and 10.7 mg of the solid catalyst component (A) obtained above was sequentially added. After adjusting the internal pressure of the autoclave to 1 kg / cm ² G, hydrogen was added at 4 kg / cm ² , and then polymerization was carried out for 1.5 hours while continuously adding ethylene so that the internal pressure of the autoclave became 11.0 kg / cm ² G. went. After the completion of the polymerization, the system was cooled, unreacted gas was expelled, polyethylene was taken out, separated from the solvent by filtration and dried.

As a result, the melt index was 0.03
g / 10 min, HLMI / MI is 109, average particle size is 35
0μ, fine particle content 1.5% by weight, bulk density 0.3
440 g of polyethylene of 5 g / cm ³ were obtained. The activity corresponds to 41000 g / g.

Example 2 [Polymerization] In the polymerization of Example 1, instead of methylaluminoxane as the catalyst component (B), 0.08 g (0.4 mmol) of tri-i-butylaluminum and methylaluminoxane were used. 1.8 in terms of aluminum atoms
Polymerization was carried out in the same manner except that milligram atoms and 11.2 mg of the solid catalyst component (A) were used.

As a result, the melt index was 0.26.
g / 10 min, HLMI / MI is 44, average particle size is 380
μ, fine particle content: 1.2% by weight, bulk density: 0.34g
231 g of polyethylene / cm ³ were obtained. Activity is 2
It was 1000 g / g.

Example 3 (a) [Preliminary polymerization] The inside of a stainless steel electromagnetic stirring type autoclave having an inner volume of 2 l was sufficiently replaced with nitrogen, and the solid catalyst component (A) obtained in Example 1 (a) was used. 02 g was suspended in 400 ml of hexane. Subsequently, 0.44 g (3.9 mmol) of triethylaluminum was sequentially added as a catalyst component (B). Thereafter, the internal temperature of the autoclave is reduced to 30.
While maintaining the temperature and the pressure at 1 to ² kg / cm ² G, propylene was supplied, 20.2 g of propylene was reacted, and the solid catalyst component (A) was prepolymerized with propylene. By this operation, 10 g of propylene was absorbed per 1 g of the solid catalyst component (A). Hexane was added to the product, and the product was washed seven times by a gradient method. Thus, a prepolymerized catalyst suspended in hexane was obtained.

(Ii) [Polymerization] Ethylene and 1-butene were copolymerized by a gas phase method using the prepolymerized catalyst obtained above. Specifically, the inside of a stainless steel electromagnetic stirring autoclave having an inner volume of 2 liters was sufficiently replaced with nitrogen, and 200 g of sodium chloride dried at 200 ° C. for 30 hours was used as a catalyst dispersion medium, and the internal temperature was adjusted to 80 ° C. Thereafter, as a component (B), methylaluminoxane was converted to 2.4 mg atom in terms of aluminum atom,
And 40.1 mg of the prepolymerized catalyst obtained above (containing 3.6 mg of the solid catalyst component (A)) were sequentially added. After adjusting the inside of the polymerization vessel to 1 kg / cm ² G with nitrogen,
While adding 2.0 kg / cm ^{2 of} hydrogen and then adjusting the butene-1 / ethylene (mol ratio) in the gas phase to be 0.20, the internal pressure of the autoclave was 19.0 kg / cm ^2.
The polymerization was carried out for 1.5 hours while continuously adding ethylene and 1-butene so as to obtain G. After completion of the polymerization, the mixture was cooled, and the unreacted gas was expelled to remove a mixture of the produced polymer and salt. The mixture was washed with pure water to dissolve the common salt and dried to obtain a polymer.

As a result, the melt index was 0.23
g / 10 min, HLMI / MI is 85, average particle size is 400
μ, fine particle content 0.7% by weight, bulk density 0.39g
/ Cm ³ , the number of ethyl branches is 21 (pieces / 1000 carbon atoms)
126 g of polyethylene was obtained. The activity per 1 g of the solid catalyst component (A) was 35,000 g / g.

Example 4 (a) [Preparation of solid catalyst component (A)] In a 1-liter glass flask equipped with a stirrer, 7.0 g (0.288 mol) of magnesium metal powder and 49.0 g (09.0 g) of titanium tetrabutoxide were added. .144 mol) and n-butanol in which 0.35 g of iodine was dissolved.
8 g (0.60 mol) was added at 90 ° C. over 2 hours,
The mixture was further stirred at 140 ° C. for 2 hours under a nitrogen seal while removing generated hydrogen gas. Then hexane 490m
was added to obtain a homogeneous solution containing Mg and the transition metal.

92.1 g of this homogeneous solution (0.1 mg as Mg)
(Equivalent to 055 mol) in a separately prepared 500 ml glass flask, and then bis (cyclopentadienyl)
4.0 g of zirconium dichloride (0.014 mo
After l) was added and dissolved, 123 ml of a hexane solution containing 0.33 mol of i-butylaluminum dichloride was added to the solution, and the mixture was stirred at 70 ° C. for 1 hour. Furthermore, after drying under a nitrogen atmosphere to remove the supernatant, solid in the catalyst component 120 ml toluene and methylaluminoxane 25.0 g (an aluminum atom in terms 0.0
73 mol) and stirred at 30 ° C. for 1 hour. Thereafter, toluene was removed under reduced pressure using an evaporator. Hexane was added to the product, and the product was washed seven times by a gradient method. Thus, the solid catalyst component (A) suspended in hexane
Was obtained. A part thereof was sampled, the supernatant was removed, and the sample was dried under a nitrogen atmosphere and subjected to elemental analysis. As a result, Ti was 2.9% by weight and Zr was 2.5% by weight.

(B) [Polymerization] The inside of a stainless steel electromagnetic stirring type autoclave having an inner volume of 2 l was sufficiently replaced with nitrogen, 1.2 l of hexane was charged, and the internal temperature was adjusted to 80 ° C. Then, the catalyst component (B)
And a slurry containing 2.2 mg atom of methylaluminoxane in terms of aluminum atom and 9.5 mg of the solid catalyst component (A) obtained above was sequentially added.
After adjusting the internal pressure of the autoclave to 1 kg / cm ² G,
Hydrogen was added at 4 kg / cm ² , and then polymerization was carried out for 1.5 hours while continuously adding ethylene so that the internal pressure of the autoclave became 11.0 kg / cm ² G. After the completion of the polymerization, the system was cooled, unreacted gas was expelled, polyethylene was taken out, separated from the solvent by filtration and dried.

As a result, the melt index was 1.50.
g / 10 min, HLMI / MI is 132, average particle size is 33
0μ, fine particle content of 1.7% by weight, bulk density of 0.3
409 g of 1 g / cm ³ of polyethylene were obtained. The activity corresponds to 43000 g / g.

Example 5 (a) [Preliminary polymerization] The solid catalyst component (A) obtained in Example 4 (a) was subjected to prepolymerization in the same manner as in Example 3 (a).

(B) [Polymerization] Ethylene and 1-butene were copolymerized by a gas phase method using the prepolymerized catalyst obtained above. Specifically, the inside of a stainless steel electromagnetic stirring autoclave having an inner volume of 2 liters was sufficiently replaced with nitrogen, and 200 g of sodium chloride dried at 200 ° C. for 30 hours was used as a catalyst dispersion medium, and the internal temperature was adjusted to 80 ° C. Thereafter, 0.44 g (2.2 mmol) of tri-i-butylaluminum as the component (B) and 38.3 mg of the prepolymerized catalyst obtained above (including 3.5 mg of the solid catalyst component (A)) were sequentially added. did. After adjusting the inside of the polymerization vessel to 1 kg / cm ² G with nitrogen, 2.0 kg / cm ^{2 of} hydrogen was added, and then butene-1 /
While adjusting ethylene (mol ratio) to 0.20, polymerization was performed for 1.5 hours while continuously adding ethylene and 1-butene so that the internal pressure of the autoclave became 19.0 kg / cm ² G. Was. After completion of the polymerization, the mixture was cooled, and the unreacted gas was expelled to remove a mixture of the produced polymer and salt. The mixture was washed with pure water to dissolve the common salt and dried to obtain a polymer. As a result, the melt index was 0.28 g / 10 min, the HLMI / MI was 50, the average particle size was 380 μm, the fine particle content was 0.9% by weight, the bulk density was 0.37 g / cm ^{3 and the} number of ethyl branches was 16 84 g of (pieces / 1000 carbons) polyethylene were obtained. The activity per 1 g of the solid catalyst component (A) was 24000 g / g.

Comparative Example 1 (a) [Preparation of catalyst] 97.5 g (equivalent to 0.059 mol as Mg) of a homogeneous solution containing Mg and a transition metal prepared in Example 4 (a) was placed in a separately prepared 500 ml glass flask. Get in,
Next, 4.4 g (0.015 mol) of bis (cyclopentadienyl) zirconium dichloride was added and completely dissolved to obtain a uniform solution. Furthermore, i
86 ml of a hexane solution containing 0.23 mol of -butylaluminum dichloride was added, and the mixture was stirred at 70 ° C for 1 hour. Hexane was added to the product, and the product was washed seven times by a gradient method. Thus, a slurry of the solid catalyst component (A) suspended in hexane was obtained. A part of it was collected, the supernatant was removed, dried under a nitrogen atmosphere, and subjected to elemental analysis.
Ti was 7.9% by weight and Zr was 6.8% by weight.

(B) [Polymerization] The inside of a stainless steel electromagnetically stirred autoclave having an internal volume of 2 liters was sufficiently replaced with nitrogen, 1.2 liters of hexane was charged, and the internal temperature was adjusted to 80 ° C. Then, the catalyst component (B)
A slurry containing 1.5 mg of methylaluminoxane in terms of aluminum atoms and 3.1 mg of the solid catalyst component (A) obtained above was sequentially added.
After adjusting the internal pressure of the autoclave to 1 kg / cm ² G,
Hydrogen was added at 4 kg / cm ² , and then polymerization was carried out for 1.5 hours while continuously adding ethylene so that the internal pressure of the autoclave became 11.0 kg / cm ² G. After the completion of the polymerization, the system was cooled, unreacted gas was expelled, polyethylene was taken out, separated from the solvent by filtration and dried.

As a result, the melt index was 0.04
g / 10 min, HLMI / MI is 64, average particle size is 110
μ, polyethylene 257 having a bulk density of 0.26 g / cm ³
g was obtained. The activity corresponds to 83000 g / g.

[0071]

The first effect of the present invention is that a polymer having a very high polymerization activity and not requiring a deashing step for removing a catalyst can be obtained. Because of its high activity, there is no need to worry about coloring or odor of the product, and purification of the polymer is not required, which is extremely economical.

The second effect of the present invention is that when copolymerization is performed, a copolymer having extremely good copolymerizability and having a narrow composition distribution can be easily produced.

The third effect of the present invention is that the molecular weight distribution can be easily controlled by the amount of the reactant used in the production of the catalyst, in particular, by the ratio of the reactant (iv) and the organoaluminum halide compound. Therefore, polymers having various physical properties can be easily produced.

The fourth effect of the present invention is that the polymer has good powder characteristics and can be produced with high productivity.
That is, the obtained polymer has few fine particles, has a large particle size, and can produce good polymer particles having little tackiness for the copolymer. For this reason, in the polymerization step, the formation of deposits in the polymerization apparatus is prevented,
In addition, in the transfer step, there is no occurrence of bridges or the like in the silo, troubles in transfer are eliminated, and granulation is performed extremely smoothly.

[Brief description of the drawings]

FIG. 1 is a flowchart of catalyst preparation.

────────────────────────────────────────────────── ─── Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) C08F 4/60-4/70

Claims (1)

(57) [Claims] 1. A process for producing a polyolefin in the presence of a catalyst comprising a transition metal compound and an organometallic compound, wherein the component (A) is selected from the group consisting of (i) a metal magnesium and a hydroxide organic compound, and an oxygen-containing organic compound of magnesium. (Ii) a general formula [Me ¹ O _a (OR ¹ ) _b X ¹ _c ] _m (the general formula
In the formula, Me ¹ is a transition metal of Group IVa of the periodic table.
Ri, R ¹ represents a hydrocarbon group having 1 to 20 carbon atoms, X ¹ is
A represents a halogen atom, and a, b and c represent a> 0 and b>
0, 4> c ≧ 0 and compatible with the valence of the transition metal
And m represents an integer. The homogeneous solution containing an oxygen-containing organic compound of at least one transition metal represented by), (iii) the general formula (cyclopentadienyl compound) _p Me ² L
_qp (In the formula, Me ² represents a transition metal of Group IVa of the periodic table.
And L is less than or equal to cyclopentadienyls coordinating to the transition metal.
Represents an outer ligand. p is the coordination of cyclopentadienyls
An integer representing a number, q represents the valence of the transition metal. p, q
Is in the range of 1 ≦ p ≦ q, and 2 when p is p ≧ 2,
Ligands of cyclopentadienyls are silylene groups,
Substituted silylene group, alkylene group, substituted alkylene group, sulfur
Two or more may be bonded via yellow. )
At least one kind of a cyclopentadienyl compound of a transition metal compound having a ligand was added and then, (iv) at least one kind of halogenated organic aluminum compound and (v) at least one or more organic aluminum that (C) polymerizing at least one or more α-olefins in the presence of a solid catalyst obtained by adding an oxy compound and a catalyst system comprising an organoaluminum compound and / or an organoaluminum oxy compound as a component (B). Of producing polyolefin.