JPS6412287B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing polyolefin using a novel polymerization catalyst.

Conventionally, in this type of technical field, the
A catalyst in which a transition metal compound such as a titanium compound is supported on magnesium halide is known from Publication No. 12105, and further Belgian Patent No. 742112
A catalyst in which magnesium halide and titanium tetrachloride are co-pulverized is known.

However, in the production of polyolefins, it is desirable for the catalyst activity to be as high as possible, and from this point of view, the method described in Japanese Patent Publication No. 39-12105 has a still low polymerization activity, while the method described in Belgian Patent No. 742112 has a fairly high polymerization activity. Although the cost has increased, improvements are still desired.

The inventors of the present invention have published Japanese Patent Publication No. 51-37194,
-48914 and Japanese Patent Publication No. 54-13276, a method for producing polyolefin _using a solid catalyst component obtained by reacting magnesium halide, Si(OR) _n However, further improvement was desired from the viewpoint that it is preferable that the molecular weight distribution of the produced polymer be extremely narrow.

Further, in the production of polyolefin, it is desirable that the bulk specific gravity of the produced polymer be as high as possible from the viewpoint of productivity. From this point of view, the above-mentioned special public service
In the method described in Publication No. 12105, the bulk specific gravity of the produced polymer is low and the polymerization activity is also unsatisfactory, and in the method described in Belgian Patent No. 742112, the polymerization activity is high but the bulk specific gravity of the produced polymer is low. Improvement is desired.

The present invention improves the above-mentioned drawbacks, and provides a novel polymerization method that can obtain polymers with high polymerization activity, narrow molecular weight distribution, and high bulk specific gravity in high yield, and can be carried out extremely easily in continuous polymerization. The present invention relates to a method for producing a catalyst and a method for polymerizing or copolymerizing an olefin using the polymerization catalyst,
Since the polymerization activity is extremely high, the monomer partial pressure during polymerization is low, and the bulk specific gravity of the produced polymer is high, so productivity can be improved, and the amount of catalyst residue in the produced polymer after polymerization is extremely small. Therefore, the catalyst removal step can be omitted in the polyolefin manufacturing process, thereby simplifying the polymer treatment process and providing an extremely economical polyolefin manufacturing method as a whole.

Furthermore, the advantages of the present invention are that although the bulk specific gravity of the produced polymer is high in terms of particle size, there are few coarse particles and fine particles of 50μ or less, so continuous polymerization reaction is facilitated, and powder This makes it easier to handle the polymer particles, such as transporting them.

Furthermore, the polymer obtained using the catalyst of the present invention has an extremely narrow molecular weight distribution and is characterized by extremely low by-products of low polymers, such as a small amount of hexane extraction. Therefore, it is possible to obtain a product of good quality, such as film grade, which has excellent blocking resistance.

The catalyst of the present invention has many of these characteristics,
Moreover, the present invention provides a novel catalyst system that improves the drawbacks of the prior art described above, and it must be said that it is surprising that these points can be easily achieved by using the catalyst of the present invention.

The present invention will be specifically explained below. That is,
[A] (1) Magnesium dihalide (hereinafter referred to as magnesium halide), (2) a compound represented by the general formula Si(OR) _n X _4-n , and (3) a titanium compound or a titanium compound A solid substance obtained by reacting a reaction product obtained by reacting a vanadium compound with a vanadium compound, and _{(4 )} a compound represented by the general formula AlR _p (In the above formula, R is a hydrocarbon residue having 1 to 24 carbon atoms, X is a halogen atom, and 0<n≦
3, 0≦m≦4 and 0<p<3.

The magnesium halide used in the present invention is substantially anhydrous and includes magnesium fluoride, magnesium chloride, magnesium bromide, and magnesium iodide, with magnesium chloride being particularly preferred.

General formula Si(OR) _n used in the present invention
X _4-n (Here, R is a hydrocarbon residue such as an alkyl group, aryl group, or aralkyl group having 1 to 24 carbon atoms,
indicates a halogen atom. m is 0≦m≦4)
Examples of compounds represented by include silicon tetrachloride, monomethoxytrichlorosilane, monoethoxytrichlorosilane, monoisopropoxytrichlorosilane, mono n-butoxytrichlorosilane, monopentoxytrichlorosilane, monooctoxytrichlorosilane, monostearoxytrichlorosilane, Chlorosilane, monophenoxytrichlorosilane, monop
-Methylphenoxytrichlorosilane, dimethoxydichlorosilane, diethoxydichlorosilane,
Diisopropoxydichlorosilane, di-n-butoxydichlorosilane, dioctoxydichlorosilane, trimethoxymonochlorosilane, triethoxymonochlorosilane, triisopropoxymonochlorosilane, tri-n-butoxymonochlorosilane, trisec-butoxymonochlorosilane, tetraethoxy Examples include silane and tetraisopropoxysilane.

Titanium compounds or titanium compounds and vanadium compounds used in the present invention Examples of the vanadium compounds include halides, alkoxy halides, alkoxides, and halogenated oxides of these metals. As a titanium compound, 4
Ti ₍ OR) _q or a hydrocarbon residue such as an aralkyl group, X represents a halogen atom, and q is 0≦q≦4.
Titanium tetrachloride, titanium tetrabromide, titanium tetraiodide,
Monomethoxytrichlorotitanium, dimethoxydichlorotitanium, trimethoxymonochlorotitanium, tetramethoxytitanium, monoethoxytrichlorotitanium, diethoxydichlorotitanium, triethoxymonochlorotitanium, tetraethoxytitanium, monoisopropoxytrichlorotitanium, diisopropoxydichlorotitanium, trichlorotitanium Isopropoxymonochlorotitanium, tetraisopropoxytitanium, monobutoxytrichlorotitanium, dibutoxydichlorotitanium, monobenxytrichlorotitanium, monophenoxytrichlorotitanium, diphenoxydichlorotitanium, triphenoxymonochlorotitanium,
Examples include tetraphenoxy titanium. As trivalent titanium compounds, titanium tetrahalides such as titanium tetrachloride and titanium tetrabromide are combined with hydrogen, aluminum, titanium, or periodic titanium.
Examples include titanium trihalides obtained by reduction with organometallic compounds of group metals. Also general formula
Ti(OR _{) r}
<r<4. Examples include trivalent titanium compounds obtained by reducing a tetravalent alkoxy titanium halide represented by ) with an organometallic compound of a group I metal of the periodic table. Examples of vanadium compounds include tetravalent vanadium compounds such as vanadium tetrachloride, vanadium tetrabromide, vanadium tetraiodide, and tetraethoxyvanadium; Examples include trivalent vanadium compounds such as trivalent vanadium compounds, vanadium trichloride, and vanadium triethoxide.

In the present invention, tetravalent titanium compounds are most preferred.

In order to make the present invention even more effective, when a titanium compound and a vanadium compound are used together, V/
The Ti molar ratio is preferably in the range of 2/1 to 0.01/1.

(1) Magnesium halide in the present invention, (2)
There are no particular restrictions on the method of reacting the compound represented by the general formula Si( _OR ) _n In the presence of temperature 20~400℃, preferably 50~
The reaction may be carried out by contacting under heating at 300°C for usually 5 minutes to 20 hours, by co-pulverization, or by an appropriate combination of these methods.

Furthermore, there is no particular restriction on the reaction order of components (1) to (3), and the three components may be reacted simultaneously, or the two components may be reacted at the same time.
After reacting the components, one other component may be reacted.

The inert solvent used at this time is not particularly limited, and any liquid organic compound that does not normally inactivate the Ziegler type catalyst can be used. Specific examples of these include propane, butane, pentane, hexane, heptane, octane, benzene, toluene, xylene, various aliphatic saturated hydrocarbons such as cyclohexane, aromatic hydrocarbons, alicyclic hydrocarbons, and ethanol and diethyl. Examples include alcohols, ethers, and esters such as ether, tetrahydrofuran, ethyl acetate, and ethyl benzoate.

The equipment used for co-pulverization is not particularly limited, but ball mills, vibration mills, rod mills, impact mills, etc. are usually used, and conditions such as mixing order, grinding time, and grinding temperature are particularly limited depending on the grinding method. rather, it can be easily determined by a person skilled in the art. It is desirable to co-mill at a temperature of usually 0°C to 200°C, preferably 20°C to 100°C for 0.5 to 30 hours. Of course, the co-grinding operation should be carried out in an inert gas atmosphere and moisture should be avoided as much as possible.

In _the present invention, the amount of the compound represented by the general formula Si(OR) _n Preferably 0.5
~10g.

In addition, the amount of titanium compound or titanium compound and vanadium compound is the amount of components (1) to (3).
It is most preferable to adjust the titanium and vanadium contained in the reaction product obtained by reacting them so that it is within the range of 0.5 to 20% by weight, and achieve a well-balanced activity per titanium and vanadium and activity per solid. In order to obtain this, a range of 1 to 10% by weight is particularly desirable.

In the present invention, (1) magnesium halide, (2) a compound represented by the general formula Si(OR) _n X _4-n ,
and (3) a reaction product obtained by reacting a titanium compound or a titanium compound with a vanadium compound is further reacted with (4) a compound represented by the general formula AlR _p X _3-p . The amount of the compound represented by the general formula AlR _p X _3-p used at this time is:
_{AlR p} Further, the reaction method at this time is not particularly limited, and for example, the reaction may be carried out in the presence of an inert hydrocarbon, or the reaction may be carried out by co-pulverization treatment.
The reaction temperature is preferably in the range of 0 to 100°C,
Further, the reaction time is preferably 5 minutes to 10 hours.

The general formula AlR _p X _3-p used in the present invention (where R
represents a hydrocarbon residue such as an alkyl group, aryl group, or aralkyl group having 1 to 24 carbon atoms, particularly preferably an alkyl group having 1 to 12 carbon atoms, and X represents a halogen atom. p is 0<p<3. ) Examples of the compound represented by: dimethylaluminum chloride, diethylaluminium chloride, diethylaluminum bromide, diethylaluminium iodide, diethylaluminum fluoride, diisopropylaluminum chloride, ethylaluminum dichloride, ethylaluminum sesquichloride, and mixtures thereof. I can do it.

The general formula AlR ₃ used in the present invention (where R is a hydrocarbon residue such as an alkyl group having 1 to 24 carbon atoms, an aryl group, an aralkyl group, particularly preferably a carbon number 1
-12 alkyl groups) are triethylaluminum, triisopropylaluminum, triisobutylaluminum, trisec-butylaluminum, tritert-
Mention may be made of butylaluminum, trihexylaluminum, trioctylaluminum and mixtures thereof. Also, the general formula AlR ₃
With the compound represented by ethyl benzoate, o
-Or organic carboxylic acid esters such as ethyl p-toluate and ethyl p-anisate can also be used in combination.

The amount of the compound represented by the general formula AlR ₃ to be used is not particularly limited, but it can usually be used in an amount of 0.1 to 1000 times the mole of the titanium compound or the titanium compound and the vanadium compound.

Olefin polymerization using the catalyst of the present invention can be carried out by slurry polymerization, solution polymerization, or gas phase polymerization, and it can be particularly preferably used for gas phase polymerization. The polymerization reaction is carried out in the same manner as an ordinary olefin polymerization reaction using a Ziegler type catalyst. That is, all reactions are carried out in the presence or absence of inert hydrocarbons, substantially deprived of oxygen, water, and the like. Olefin polymerization conditions are temperature
The temperature is 20 to 120°C, preferably 50 to 100°C, and the pressure is normal pressure to 70Kg/cm ² , preferably 2 to 60Kg/cm ² . Molecular weight can be adjusted by polymerization temperature,
Although it can be controlled to some extent by changing polymerization conditions such as the molar ratio of catalysts, it is effectively achieved by adding hydrogen to the polymerization system. of course,
Using the catalyst of the present invention, two-stage or more multi-stage polymerization reactions with different polymerization conditions such as hydrogen concentration and polymerization temperature can be carried out without any problems.

The method of the present invention is applicable to the polymerization of all olefins that can be polymerized with Ziegler's catalyst, and α-olefins having 2 to 12 carbon atoms are particularly preferred, such as ethylene, propylene, 1-butene, hexene-1,4-methyl Homopolymerization of α-olefins such as pentene-1 and octene-1, ethylene and propylene, ethylene and 1-butene, ethylene and hexene-1, ethylene and 4-methylpentene-1, ethylene and octene-1, propylene and 1
- Suitably used for copolymerization of butene, copolymerization of ethylene and two or more other α-olefins, etc.

Copolymerization with dienes is also preferably carried out for the purpose of modifying polyolefins. Examples of diene compounds used at this time are butadiene,
Examples include 1,4-hexadiene, ethylidene norbornene, and dicyclopentadiene.

Examples will be described below, but these are for illustrative purposes to carry out the present invention, and the present invention is not limited thereto.

Example 1 (a) Preparation of solid catalyst component 15 g of commercially available anhydrous magnesium chloride, 3.1 g of diethoxydichlorosilane,
Then, 5.6 g of tetraisopropoxytitanium was added and ball milling was performed at room temperature for 16 hours under a nitrogen atmosphere. Solid powder obtained after ball milling
(A) 1g contained 39mg of titanium.

Next, in a 300 ml three-neck flask purged with nitrogen, 100 ml of hexane, 10 g of the above solid powder (A) and 2 g of ethylaluminum sesquichloride (Al/Ti
(molar ratio) = 2) and reacted for 2 hours under refluxing hexane. After the reaction was completed, the mixture was allowed to stand still and the supernatant liquid was removed, and then the solid component was washed with hexane to obtain a solid catalyst component (B).

(b) Polymerization A stainless steel autoclave was used as the gas phase polymerization apparatus, a loop was created with a blower, a flow controller, and a dry cyclone, and the temperature of the autoclave was adjusted by flowing hot water through the jacket.

The above solid catalyst component (B) was supplied to an autoclave adjusted to 80°C at a rate of 50 mg/hr and triethylaluminum 2 mmol/hr, and the butene-1/ethylene ratio (molar ratio) in the gas phase of the autoclave was set to 0.27. In addition, hydrogen is added to 15% of the total pressure.
Polymerization was carried out by supplying each gas while adjusting the following, and by circulating the gas in the system using a blower to maintain the total pressure at 10 kg/cm ² ·G. The produced ethylene copolymer has a bulk specific gravity of 0.41, a melt index (MI) of 1.1, and a density
It was 0.9201.

The catalyst activity was extremely high at 473,000g copolymer/gTi.

After 10 hours of continuous operation, the autoclave was opened and the interior was inspected, but the inner walls and stirrer were clean with no polymer attached at all.

This copolymer has an F value expressed as the ratio of melt index MI2.16 measured at 190°C under a load of 2.16 kg and melt index MI10 measured under a load of 10 kg using the method of ASTM-D1238-65T.
The R. value (FR=MI10/MI2.16) was 7.1, and the molecular weight distribution was extremely narrow.

Furthermore, when a film of this copolymer was extracted in boiling hexane for 10 hours, the hexane extraction amount was 1.0 wt%, which was an extremely small amount.

Comparative Example 1 Solid powder (A) obtained in Example 1 as a solid catalyst component
Polymerization was carried out in the same manner as in Example 1, except that 50 mg/hr of ethylene butene was supplied at a rate of 50 mg/hr.
A copolymer was obtained. Catalytic activity is 146000g copolymer/
gTi, and its activity was lower than that of Example 1.

The FR value of this copolymer was 7.3, and the amount of hexane extracted from the film was 1.5 wt%.

Comparative Example 2 The solid powder (A) obtained in Example 1 was put into a 300 ml three-necked flask purged with nitrogen, along with 100 ml of hexane, and then 0.9 g of triethylaluminum (Al/
Ti (molar ratio)=1) was added thereto and the mixture was reacted for 2 hours under refluxing hexane. After the reaction was completed, the mixture was allowed to stand and the supernatant liquid was removed, and then the solid component was washed with hexane to obtain a solid catalyst component (C).

Polymerization was carried out in the same manner as in Example 1, except that the solid catalyst component (C) was supplied at a rate of 50 mg/hr, and ethylaluminum sesquichloride was supplied at a rate of 2 mmol/hr instead of triethylaluminum.
Bulk specific gravity 0.25, melt index 0.8, density
A copolymer of 0.9251 was obtained. The catalyst activity was 8650g copolymer/gTi, which was significantly lower than in Example 1.

Comparative Example 3 Solid powder (A) obtained in Example 1 as solid catalyst component
was supplied at a rate of 50 mg/hr, and triethylaluminum and ethylaluminum sesquichloride were supplied at 2 mmol/hr and ethylaluminum sesquichloride as organoaluminum compounds.
Polymerization was carried out in the same manner as in Example 1 except that the copolymer was supplied at a rate of 2 mmol/hr to obtain a copolymer having a bulk specific gravity of 0.31, a melt index of 0.9, and a density of 0.9201.

The FR value of this copolymer was 7.9, and the amount of hexane extracted from the film was 3.3 wt%.

Example 2 A solid catalyst component was synthesized in the same manner as in Example 1, except that 1.1 g of diethylaluminum chloride was used instead of ethylaluminum sesquichloride.

Gas phase polymerization was carried out in the same manner as in Example 1 except that the above solid catalyst component was supplied at a rate of 50 mg/hr.
An ethylene-butene-1 copolymer of 0.9211 was obtained.
The catalyst activity was 534,000 g copolymer/g Ti, which was extremely high.

After 10 hours of continuous operation, the autoclave was opened and the interior was inspected, but the inner walls and stirrer were clean with no polymer attached at all.

The FR value of this copolymer was 7.0, and when the film was extracted in boiling hexane for 10 hours,
The amount of hexane extracted was 0.9wt%, which was an extremely small amount.

Example 3 10 g of anhydrous magnesium chloride and 4.1 g of diisopropoxydichlorotitanium were placed in the ball mill pot described in Example 1, and ball milling was carried out at room temperature in a nitrogen atmosphere for 16 hours to obtain a solid powder (D). Then, 100 ml of hexane, 10 g of the above solid powder (D), and 4.3 g of tetraethoxysilane were placed in a three-neck flask equipped with a stirrer and the atmosphere was replaced with nitrogen, and the mixture was reacted for 2 hours under refluxing hexane. After the reaction was completed, ethylaluminum sesquichloride was added and the mixture was further reacted for 2 hours under refluxing hexane. After the reaction is complete, let it stand, remove the supernatant, and then wash with hexane to remove titanium in 1 g.
A solid catalyst component containing 35 mg was obtained.

Polymerization was carried out in the same manner as in Example 1, except that the solid catalyst component was fed at a rate of 50 mg/hr. The produced ethylene copolymer has a bulk specific gravity of 0.37 and a density of
The melt index was 0.9223 and the melt index was 1.3. The catalyst activity was extremely high at 546,000 g/copolymer/gTi.

Furthermore, the FR value of this copolymer was 7.2, and when the film was extracted in boiling hexane for 10 hours, the hexane extraction amount was 1.2 wt%, which was an extremely small amount.

The stainless steel autoclave equipped with an induction stirrer from Example 4 2 was purged with nitrogen, 1000 ml of hexane was added, 0.8 mmol of triethylaluminum and 10 mg of the solid catalyst component (B) obtained in Example 1 were added, and the temperature was raised to 90°C with stirring. It was warm. The vapor pressure of hexane is 2Kg/ ^cm2・G, but the total pressure of hydrogen is 4.8Kg/cm2.
The pressure was charged until the pressure reached cm ² .G, and then ethylene was charged until the total pressure reached 10 kg/cm ² .G to initiate polymerization. Ethylene was continuously introduced so that the total pressure was 10 Kg/cm ² ·G, and polymerization was carried out for 1 hour. After polymerization, the polymer slurry was transferred to a beaker, hexane was removed under reduced pressure, and the melt index was 1.4 and the density was
206 g of white polyethylene with a bulk specific gravity of 0.9627 and 0.36 was obtained. Catalyst activity is 101600g polyethylene/gTi.hr.
C ₂ H ₄ pressure, 3960g polyethylene/g solids. hr.C ₂ H ₄
Polyethylene with high pressure and bulk specific gravity was obtained with extremely high activity.

The FR value of the obtained polyethylene was 8.1, the molecular weight distribution was extremely narrow, and the hexane extraction amount was 0.17 wt%.

Comparative Example 4 Using 10 mg of the solid catalyst component used in Comparative Example 1, polymerization was carried out for 1 hour in the same manner as in Example 4 to obtain 83 g of white polyethylene having a melt index of 1.6, a density of 0.9638, and a bulk specific gravity of 0.32. Catalyst activity is 39900g
Polyethylene/gTi·hr.C ₂ H ₄ pressure, 1600 g polyethylene/g solid, hr.C ₂ H ₄ pressure, and the activity was lower than in Example 4.

The FR value of the obtained polyethylene was 8.2, and the hexane extraction amount was 0.25 wt%.

Example 5 A catalyst component was synthesized in the same manner as in Example 1, except that 3.8 g of titanium tetrachloride was used instead of 5.6 g of tetraisopropoxytitanium, and 40 mg was added to 1 g of solid powder. A solid powder (A) containing titanium was obtained.

A solid catalyst component was prepared from the solid powder (A) in the same manner as in Example 1.
(B) was synthesized.

Using the above solid powder (B), gas phase polymerization was performed in the same manner as in Example 1, and the melt index was 1.2.
An ethylene copolymer with a bulk specific gravity of 0.39 and a density of 0.9195 was obtained. The catalyst activity was extremely high at 528,000g copolymer/gTi.

After 10 hours of continuous operation, the autoclave was opened and the interior was inspected, but the inner walls and stirrer were clean with no polymer attached at all.

In addition, this copolymer has an FR value of 7.4, and when the film was extracted in boiling hexane for 10 hours,
The amount of hexane extracted was 1.5wt%, which was an extremely small amount.

Example 6 A solid powder was synthesized in the same manner as in Example 1, except that 3.8 g of titanium tetrachloride and 1.5 g of triethoxyvanadyl were used in place of 5.6 g of tetraisopropoxy titanium. 39mg in 1g
A solid powder (A) was obtained containing 50 mg of titanium and 14 mg of vanadium.

A solid catalyst component was prepared from the solid powder (A) in the same manner as in Example 1.
(B) was synthesized.

Using the above solid powder (B), gas phase polymerization was performed in the same manner as in Example 1, and the melt index was 0.8.
An ethylene copolymer with a bulk specific gravity of 0.41 and a density of 0.9211 was obtained. The catalyst activity was extremely high at 466,000g copolymer/gTi.

After 10 hours of continuous operation, the autoclave was opened and the interior was inspected, but the inner walls and stirrer were clean with no polymer attached at all.

The FR value of this copolymer was 7.2, and when the film was extracted in boiling hexane for 10 hours,
The amount of hexane extracted was 1.1wt%, which was an extremely small amount.

Example 7 The following gas phase polymerization was carried out using the apparatus described in Example 1. The solid powder (A) obtained in Example 1 was fed into an autoclave prepared at 60°C at a rate of 80 mg/hr and triethylaluminum at a rate of 5 mmol/hr. Propylene was also fed into the autoclave, and the gas in the system was removed using a blower. is circulated to a total pressure of 7 kg/
Polymerization was carried out in cm ² . The polypropylene produced had a bulk specific gravity of 0.38. Also, the catalyst activity is 165000g
It was polypropylene/gTi.

After 10 hours of continuous operation, the autoclave was opened and the interior was inspected, but the inner walls and stirrer were clean with no polymer attached at all.

[Brief explanation of drawings]

FIG. 1 is a flowchart showing an example of catalyst preparation in olefin polymerization of the present invention.

Claims (1)

[Claims] 1 [A] (1) Magnesium dihalide, (2) a compound represented by the general formula Si(OR) _n X _4-n , and (3) a titanium compound or a titanium compound and a vanadium compound reacted. The reaction product obtained by the reaction is further reacted with (4) a compound represented by the general formula AlR _{p X 3-p} , and [B] a catalyst consisting of the compound represented by the general formula AlR In the formula, R is a hydrocarbon residue having 1 to 24 carbon atoms, X is a halogen atom, and 0<n≦
3, 0≦m≦4 and 0<p<3.