JPS59179607A - Production of polyolefin - Google Patents

Abstract

PURPOSE:To produce spherical polyolefin particles of a uniform particle size in high yields, by using a catalyst comprising an organomethallic compound component and a solid catalyst component containing a support obtained by contacting a magnesium dialkoxide with combinations of a specified silicon compound and an alcohol in two stages. CONSTITUTION:A reaction product obtained by (i) reacting, by contact, a magnesium dialkoxide (e.g., magnesium dimethoxide) with both a silicon compound of formula I (e.g., silicon tetrachloride or trichloromethoxy-silane) and an alcohol (e.g., cyclopentanol), and (ii) contacting the produced solid substance with both a silicon compound of formula II and an alcohol (e.g., isopropanol) is used as a support. (In formulas I and II, X<1> and X<2> are each a halogen, R<1> and R<2> are each an alkyl, alkenyl, aryl, or the like, and n and m are each 0-4.) Namely, an alpha-olefin is polymerized in the presence of a catalyst obtaoned by combining (A) solid catalyst component obtained by impregnating the above support with a titanium metal with (B) an organometallic compound.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing polyolefins, and more particularly to a method for efficiently producing polyolefins with various excellent properties by polymerizing olefins in the presence of a catalyst using a specific solid carrier.

Conventionally, various methods have been known for producing polyolefins using a catalyst consisting of a solid catalyst component in which a transition metal such as titanium is supported on a solid carrier and an organometallic compound. It is known that highly active catalysts can be obtained by treating the magnesium compound constituting the solid support with a silicon compound or with a silicon compound and an electron donor such as alcohol. Alternatively, after co-pulverizing a magnesium compound and a silicon compound, the magnesium compound is mixed with a silicon compound, etc. again in the presence of a titanium compound (Japanese Unexamined Patent Publication No. 5'4-78786), or the magnesium compound is treated with alcohol and a silicon compound. After that, by using a catalyst obtained by reacting a silicon compound twice in the presence of a titanium halide (Japanese Unexamined Patent Publication No. 149307/1983), the catalytic activity and production can be improved. It is known that the particle size distribution of polymers can be improved to some extent.

However, the above methods do not provide sufficient improvement effects;
In practical terms, this was not yet satisfactory.

The present inventors have conducted extensive research in order to develop a method that is highly productive and still allows obtaining a polymer having a preferable particle size distribution. As a result, they found that the object could be achieved by using a magnesium dialkoxide that was subjected to contact treatment twice with a specific silicon compound and alcohol as a carrier for the solid catalyst component, and completed the present invention. reached. That is, the present invention is (A)! A solid catalyst component in which a transfer metal is supported on a solid carrier 1, and (B)
In the method for producing a polyolefin using a catalyst containing an organometallic compound as a main component, the solid carrier is magnesium dialkoxide, general formula X"n5i(OR"
)44 (In the formula, xl is a halogen atom, Bl is an aliphatic alkyl group, an alicyclic alkyl group, an alkenyl group, an aryl group, or an aralkyl group, and n is 0≦n≦4.) The compound and the alcohol are catalytically reacted, and then the resulting solid material is expressed by the general formula X2mSi
(OR2)4-m (wherein, X2 is a halogen atom, B2 is an aliphatic alkyl group, an alicyclic alkyl group, an alkenyl group,
The group represents an aralkyl group, and m is 0≦m≦
It is 4. The present invention provides a method for producing a polyolefin, which is characterized by using a reaction product obtained by contacting a silicon compound represented by the above formula with an alcohol.

The solid support for the solid catalyst component, which is component (A) of the catalyst used in the method of the present invention, is prepared by a two-step catalytic reaction. First, in the first step, magnesium dialkoxide, a silicon compound, and an alcohol are Make the champion react to contact. In this catalytic reaction, there are no particular restrictions on the operating order and conditions, and they may be carried out as appropriate. For example, the above-mentioned magnesium dialkoxide, silicon compound, and alcohol may be mixed simultaneously and subjected to the catalytic reaction. A preferred procedure is to first mix the magnesium dialkoxide silicon compound and then add the alcohol dropwise over a period of several minutes to several hours.
Gradually raise the temperature to about 50-100'C, and then
Let it react for about an hour.

The magnesium dialkoxide used here is usually an aliphatic or alicyclic dialkoxide having 1 to 20 carbon atoms, preferably 1 to 8 carbon atoms. More specific examples include magnesium dimethoxide, magnesium jetoxide, magnesium dibroboxide, magnesium dibutoxide, and magnesium dicyclohexoxide.

These magnesium dialkoxides can be easily obtained by known methods, but the particle size is usually 1 to 50.
Use one with a diameter of 0μ. Although this magnesium dialkoxide may be used as it is, it may be suspended in an inert solvent such as pentane, hexane, heptane, etc. to a concentration of 50 to 500.
Preferably, the slurry is used as a slurry of about f/.

On the other hand, as the silicon compound used in the above first step catalytic reaction, a compound represented by the general formula represents a hydrocarbon group, particularly an aliphatic alkyl group having 1 to 8 carbon atoms, an alicyclic alkyl group, an alkenyl group, an aryl group, or an aralkyl group. Also, n is a real number in the range of ≦n≦4. Typical examples of such silicon compounds include tetrachlorosilane (silicon tetrachloride), tetrabromosilane, trichloromethoxysilane, dichlorojethoxysilane, etc., and these can be used alone or as a mixture. The amount of the silicon compound to be added is not particularly limited, but it should be an amount corresponding to a halogen/magnesium (atomic ratio) of 1 or less, preferably in the range of 115 to 1, and more preferably 1/1 or less, relative to the magnesium dialkoxide. In addition, the alcohol used in the first stage contact reaction mentioned above is
It is a straight-chain or side-chain aliphatic alcohol or alicyclic alcohol, preferably a 17th or secondary alcohol having 1 to 8 carbon atoms, especially an alicyclic alcohol. Specific examples include methanol, ethanol, propatool, impropatool, butanol, isobutanol, amyl alcohol, octatool, cyclopenta/-ruacyclohexanol, cyclo-pentanol, among which cyclopentanol is particularly preferred. , cyclohexanol, cycloheptatool, etc. are preferred. The amount of this alcohol added is usually at least 0.1 times the molar amount of the red sea bream chromium dialkoxide, and there is no particular restriction on the upper limit of this amount added. However, in general, it is sufficient to use a value around the same level as the halogen contained in the silicon compound. If the amount of alcohol used is too small, the desired improvement in catalytic activity and bulk density of the resulting polymer will not be achieved sufficiently.

The mDX used in the first-stage contact reaction is not particularly limited as long as it is inert and does not react with the above-described magnesium dialkoxide, silicon compound, and alcohol, and may be an aliphatic hydrocarbon.

Examples include various solvents such as alicyclic hydrocarbons. Specifically, butane, pe〉tan, hexa〉, and hepta〉.

Cyclohexane and the like are preferred. This contact reaction can also be carried out without a solvent; in this case, for example, the magnesium dialkoxide, silicon compound, and alcohol may be directly mechanically mixed in a predetermined proportion using a ball mill or the like.

In the present invention, the solid substance thus obtained is used in the next reaction as it is in the reaction solution of the first stage, or after washing and separating the solid substance. The solid material obtained in the first stage contact reaction is then subjected to the second stage contact reaction.
It is also effective to react with a compound containing a transition metal such as titanium, zirconium, vanadium, chromium, molybdenum, tungsten, manganese, iron, nickel, cobalt, etc., preferably a titanium compound, before subjecting to the reaction. The titanium compound used here may be tetravalent, trivalent, or divalent halogen-containing titanium, specifically 'r1
a4 + TiBr4 + Ti(OR3)04 +
Ti(ORsuat2゜Ti(ORtsuCJt, TiC
4, Ti[r3. TiCQ etc. (where R3 is a methyl group, ethyl group, isopropyl group, n-butyl group,
Indicates a hydrocarbon group such as an allyl group or a phenyl group. ) can be given.

In the present invention, the solid substance obtained in the first stage contact reaction or the solid substance obtained by further reacting a transition metal-containing compound is brought into contact with a silicon compound and alcohol again to perform the second stage contact reaction. Conduct a contact reaction. Solid substance in this case.

There is no particular restriction on the order of contact between the silicon compound and the alcohol, and the two may be mixed at the same time, or the solid substance and the silicon compound may be reacted, and then the alcohol may be added to the reaction system. Preferably, first, the silicon compound is added and mixed to the above-mentioned solid substance in the state of the first-stage reaction dispersion, and then the alcohol is added dropwise over a period of several minutes to several hours, and the temperature is gradually heated to 50 to 100°.
The temperature is raised to about K, and the reaction is continued for about 1 to 5 hours. In this second stage contact reaction, if the solid substance washed and separated from the first stage reaction system is used,
Preferably, a suitable inert solvent is added to form a slurry of the solid material, and the silicon compound and further alcohol are added thereto.

Hexane is also used when adding alcohol.

An inert solvent such as heptane can also be added to the reaction system (usually in a mixed state). Note that this second stage contact reaction can also be carried out without a solvent as in the first stage.

The silicon compound used in the second stage reaction has the general formula
2mSi (OR2), a compound represented by -m is applicable. In this formula, x2 represents a halogen atom such as chlorine, bromine, or iodine, and B2 represents a hydrocarbon group, particularly an aliphatic alkyl group having 1 to 8 carbon atoms, an alicyclic alkyl group, an alkenyl group, an aryl group, or an aralkyl group. shows. Also m
is a real number in the range 0≦m≦4. Such a silicon compound may be the same as or different from the silicon compound used in the first step reaction described above. in particular,
Examples include tetrachlorosilane, detrapromsilane, trichlormethoxysilane, dichlorjethoxysilane, etc., and these can be used alone or in combination. Further, the amount of this silicon compound added is not particularly limited, but it should be an amount corresponding to /10 gen/magnesium (atomic ratio) of 5 or less, preferably 05 to It should be in the range of 3.

On the other hand, the alcohol used in the second step reaction is a direct or side chain aliphatic alcohol or alicyclic alcohol, preferably a C1-C8 primary or secondary alcohol.
Alcohols, particularly preferably Impropatool and B
Examples include aliphatic secondary alcohols such as eQ-butanol and tertiary alcohols such as tert and -butamele.

The amount of alcohol to be added is usually 0.1 times the mole or more relative to the above-mentioned magnesium dialkoxide, and although there is no particular restriction on the upper limit of this amount, it is generally used in the second stage reaction. As a guideline, the amount should be around the same amount as the halogen contained in the silicon compound used for.

Furthermore, in this second stage reaction, primary amines such as isopropylamine, n-butylamine, propatoolamine, benzylamine, toluidine, etc., and secondary amines such as dipropylamine, di-n-butylamine, etc. are added as necessary. It is also effective to add it to the reaction system. The solid carrier obtained in this way has a marimo-like morphology in which fibrous substances are entangled, is a solid with a uniform particle size distribution, and is completely new (Figs. 1 to 6). reference)
. It also has a large specific surface area and is highly active as a catalyst carrier for supporting various active metals, making it widely useful.

In the present invention, the reaction product obtained through the first and second steps is used as a solid support, and titanium zirconium,
A compound containing a transition metal such as vanadium, chromium, molybdenum, tungsten, manganese, nickel, ortho, preferably halogen-containing titanium as described above, is supported to form the solid catalyst component (A). The compounding amount of the compound is not particularly limited, but it is 0.01 to 20 times the amount of magnesium dialkoxide used as the raw material for producing the solid carrier, preferably 0.1 to 20 times in mole.
It may be selected within a 10-fold molar range.

In order to support a transition metal on a solid support, this solid support and a compound containing a transition metal such as titanium are mixed in an inert solvent such as hexane or heptane at 0 to 200°C under normal pressure or pressure. Preferably 50-150°C (
7) The reaction may be carried out under stirring conditions for an appropriate period of time. Moreover, this supporting treatment can also be carried out without a solvent.
Mechanical mixing using a ball mill or the like may be performed at the above temperature.

The organometallic compound which is the component (B) of the catalyst used in the method of the present invention may be of various types and is not particularly limited. The metals contained in this organometallic compound include metals of Groups 1 to 3 of the periodic table, such as lithium, sodium, potassium, zinc, and cadmium.

Among them, aluminum is particularly preferred. Specific examples of organometallic compounds include alkyllithium such as methyllithium, ethyllithium, propyllithium, butyllithium, dimethylzinc, diethylzinc, and diethylzinc.

There are dialkylzincs such as dibutylzinc, and organoaluminum compounds such as general formula A, tR3kX
3. - is widely used.

R3 is an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group or an aryl group, k is a real number between 1 and 6, and X3 represents a halogen atom such as chlorine or bromine. Specifically, trialkylaluminium compounds such as trimethylaluminum, triethylaluminum, triisopropylaluminum, triisobutylaluminum, trioctylaluminum, and diethylaluminium monochloride.

Dialkyl aluminum monohalides such as diisopropylaluminum monochloride, diisobutyl aluminum monochloride, and dioctyl aluminum monochloride are preferred, and mixtures thereof are also preferred.

In the method of the present invention, a dispersion of the above solid catalyst component as component (A) and an organometallic compound as component (B) are added to the reaction system to form a catalyst, and an olefin is introduced into the catalyst for polymerization.

There are no particular restrictions on the polymerization method and conditions, including solution merging,
Both suspension polymerization and gas phase polymerization are possible, and both continuous polymerization and discontinuous polymerization are possible. The addition of the catalyst component is determined by solution polymerization or cloud polymerization (for example, in the case of cloud polymerization, component (A) is converted to 0 in terms of transition metals such as titanium atoms).
．． 001-10 mmol/t% preferably 0.00
5 to 0.5 mmol/l, and the ratio of component (B) to the transition metal such as titanium atom in component (A) is 1 to 100 (mole ratio), preferably 10 to 500 (mole ratio). The olefin pressure in the reaction system is preferably normal pressure to 50 kg/ci, and the reaction temperature is 50 to 200°C, preferably 50 to 200°C.
The temperature shall be 150°C. Molecular group adjustment during polymerization can be carried out by known means, such as hydrogen. The reaction time may be appropriately selected from 10 minutes to 10 hours, preferably from 60 minutes to 5 hours.

The olefin that can be polymerized by the method of the present invention usually has a general formula of CH=C2H4 (R4 is hydrogen or has 1 to 2 carbon atoms).
0 alkyl group or cycloalkyl group. ), such as linear monoolefins such as ethylene, propylene, butene-1, hexene-1, octene-1, branched monoolefins such as 4-methyl-petene-1, There are various other olefins, and the present invention can be effectively used for homopolymerization of these or copolymerization of various olefins.

According to the method of the present invention, the activity of the catalyst used is extremely high and there is no need for a deashing step, and the polyolefin obtained is spherical and has a preferable particle size distribution with uniform particle sizes. The corners become smaller. Therefore, Giliolefin powder has high fluidity and is easy to handle.
At the same time, it becomes a high-value product.

Next, Examples and Comparative Examples of the present invention will be shown. All operations in the Examples and Comparative Examples below were performed under an argon stream.

Examples 1 to 4 and Comparative Examples 1 to 5 (1) Preparation of solid catalyst components Dried 150- and magnesium jetoxide (average particle size 12μ) in a 500rrLl fourth flask at 20°C. wo10.051-(88
mmol) and suspended, and as a first step reaction, a predetermined amount of silicon tetrachloride was added, and a mixture of the predetermined alcohol and 40 ml of n-hexadiene (primary reagent dehydrated with a molecular sieve) was mixed with 1 After dripping for a while,
The temperature was raised to about 70°C over 30 minutes, and the reaction was allowed to occur for 2 hours in a relaxed state.

The temperature was lowered to 20°C while the formed precipitate was dispersed, and a predetermined amount of silicon tetrachloride was added as a second step reaction, and the predetermined alcohol and n-hexane (primary reagent) were mixed with a molecular sieve. 1 of the mixture of 40+++l (dehydrated)
After the dropwise addition over a period of time, the temperature was raised to about 70°C over 60 minutes, and the reaction was allowed to proceed for an additional 2 hours in a relaxed state to obtain a solid support.

Next, add 41.8% titanium tetrachloride to this system. (220
millimoles) and stirred at about 70°C for 3 hours, then cooled to around 40°C and thoroughly washed with n-hexane until no rogens were detected in the liquid phase to remove the solid catalyst component. Obtained. The conditions and results are shown in Table 1. In addition, micrographs 1 to 6 of the solid support obtained in Example 1 are
As shown in the figure.

(2) Production of polyethylene Dehydrated n-hexane (dehydrated primary reagent with molecular sieve) 4001d,) 2 mmoles of diethylaluminum were placed in a 1 mmol autoclave with a hydrogen pressure of 3 kl? /cd, ethylene pressure 5 kg /
80°C while continuously supplying ethylene so that
Polyethylene was obtained by polymerization for 1 hour. The results are shown in Table 2.

[Brief explanation of drawings]

1 to 3 are micrographs of the solid support obtained in Example 1. The magnification is 1000x for Figure 1 and 300x for Figure 2.
0x, Figure 5 1oooox. Patent applicant Idemitsu Kosan Co., Ltd. Agent Patent attorney Fujibe Kubota 2 1X10 mrn Figure 2 33 x 1 x 3 mm 1XiQ3rT1m

Claims (3)

[Claims] (1) In a method for producing a polyolefin using (A) a solid catalyst component in which an a-transfer metal is supported on a solid carrier and (B) a catalyst mainly composed of an organometallic compound, the solid carrier is magnesium dialkoxide. ,
General formula
It represents an alkenyl group, an aryl group or an aralkyl group, and n is 0≦n≦4. ) A silicon compound represented by ) and an alcohol are catalytically reacted, and the resulting solid substance is then reacted with the general formula
It represents an alicyclic alkyl group, an alkenyl group, an aryl group, or an aralkyl group, and m is 0≦m≦4. ] A method for producing a polyolefin, the method comprising using a reaction product obtained by contacting the silicon compound represented by the above with an alcohol. (2) The method according to claim 1, wherein the transition metal is titanium. (3) The method according to claim 1, wherein the organometallic compound is an organoaluminum compound.