JP3542431B2 - Olefin polymerization catalyst and method for producing olefin polymer using the same - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an olefin polymerization catalyst and a method for producing an olefin polymer using the same. The catalyst for olefin polymerization of the present invention is a novel catalyst which is easy to produce and industrially advantageous.
[0002]
[Prior art]
An olefin polymerization catalyst in which a titanium compound or a chromium compound is supported on magnesium chloride, silica, alumina, zeolite, or the like is known. U.S. Pat. No. 4,665,045 describes that a column-insertable layered clay composition produced using a chromium compound can be used for olefin polymerization.
[0003]
[Problems to be solved by the invention]
In the field of olefin polymerization catalysts, it is desired to provide new catalysts, and the present invention has been made for the purpose of providing new olefin polymerization catalysts.
[0004]
[Means for Solving the Problems]
The present invention provides an olefin polymerization catalyst [A] produced by sequentially performing the following steps (I) to (IV):
(I) at least one compound selected from the group consisting of clays, clay minerals and ion-exchangeable layered compounds, containing at least one atom selected from the group consisting of transition metal atoms belonging to Groups 4 to 6 of the periodic table; Contacting a salt soluble in an aqueous or acidic aqueous solution comprising a cation and at least one anion selected from the group consisting of a halogen atom, an inorganic acid and an organic acid anion to obtain a solid product ,
(II) washing the solid product with water until the washing solution has a pH of 3 to 7;
(III) drying the washed solid product;
(IV) contacting the dried solid product with an organoaluminum compound to obtain a catalyst [A];
And a method for producing an olefin polymer in the presence of the olefin polymerization catalyst [A]. Further, the olefin polymerization catalyst [A] and an organoaluminum compound [ B] in the presence of an olefin polymer.
[0005]
BEST MODE FOR CARRYING OUT THE INVENTION
In the present invention, at least one compound selected from the group consisting of clay, clay minerals and ion-exchangeable layered compounds is used. Here, the compounds contained in the clay, the clay mineral and the ion-exchangeable layered compound may each be classified in an overlapping manner, but the compound used in the present invention is at least classified into any of these. It is.
Clay is usually composed mainly of clay minerals. An ion-exchangeable layered compound is a compound having a crystal structure in which planes formed by ionic bonds and the like are stacked in parallel with a weak binding force to each other, and means a compound whose contained ions are exchangeable. Most clays are ion-exchangeable layered compounds. Further, these clays, clay minerals or ion-exchangeable layered compounds are not limited to natural products and may be artificially synthesized products.
[0006]
Specific examples of clays and clay minerals include allophanes such as allophane, kaolins such as dickite, nacrite, kaolinite, and anoxite, halloysites such as metahalloysite and halloysite, and serpentines such as chrysotile, lizardite, and antigolite. Stone group, montmorillonite, zaukonite, beidellite, nontronite, saponite, smectite such as hectorite, vermiculite mineral such as vermiculite, illite, sericite, mica mineral such as chlorite, attapulgite, sepiolite, paigolskite, bentonite, kibushi Clay, gairome clay, hisingelite, pyrophyllite, ryokudeite group, and the like. These may form a mixed layer.
[0007]
Of these, preferably kaolins such as dickite, nacrite, kaolinite, and anoxite, halloysites such as metahaloisite, halloysite, serpentine groups such as chrysotile, lizardite, and antigolite, montmorillonite, zauconite, beidellite, nontroth Knights, saponites, smectites such as hectorite, vermiculite minerals such as vermiculite, mica minerals such as illite, sericite, sea chlorite, etc., and particularly preferably montmorillonite, zauconite, beidellite, nontronite, saponite, hectorite, etc. Smectite. Examples of artificial synthetic substances include synthetic hectorite, synthetic mica (mica), and synthetic saponite.
[0008]
Examples of the ion-exchange layered compound include an ionic crystalline compound having a layered crystal structure such as a hexagonal close-packing type, an antimony type, a CdCl ₂ type, and a CdI ₂ type. Specific examples of the ion-exchange layered compound include α-Zr (HAsO ₄ ) ₂ .H ₂ O, α-Zr (HPO ₄ ) ₂ , α-Zr (KPO ₄ ) ₂ .3H ₂ O, α-Ti ( HPO ₄ ) ₂ , α-Ti (HAsO ₄ ) ₂ · H ₂ O, α-Sn (HPO ₄ ) ₂ · H ₂ O, γ-Zr (HPO ₄ ) ₂ , γ-Ti (HPO ₄ ) ₂ , γ -Ti (NH ₄ PO ₄₎ polyvalent metal crystalline acid salts of such ₂ · H ₂ O and the like.
These may be used as they are in the step (I) without any particular treatment, or may be used with a ball mill, a sieve, inorganic acids such as hydrochloric acid, sulfuric acid, phosphoric acid, etc., and organic acids such as formic acid, acetic acid, benzoic acid, etc. May be used after performing a treatment such as an acid treatment by contacting with a varnish. Further, they may be used alone or as a mixture of two or more.
[0009]
The salt used in the present invention includes a cation containing at least one atom selected from the group consisting of transition metal atoms belonging to Groups 4 to 6 of the periodic table, and a group consisting of a halogen atom, an anion of an inorganic acid and an organic acid. And at least one anion selected from the group consisting of a compound soluble in a water-soluble or acidic aqueous solution. Here, the acidic aqueous solution means an aqueous solution having a pH of 6 or less, preferably a pH of 3 or less.
Specifically, Ti (OOCCH ₃ ) ₄ , Ti (CO ₃ ) ₂ , Ti (NO ₃ ) ₄ , Ti (SO ₄ ) ₂ , TiF ₄ , TiCl ₄ , TiBr ₄ , TiI ₄ , Zr (OOCCH ₃ ) ₄ , Zr (CH ₃ COCHCOCH ₃ ) ₄ , Zr (CO ₃ ) ₂ , Zr (NO ₃ ) ₄ , Zr (SO ₄ ) ₂ , ZrF ₄ , ZrCl ₄ , ZrBr ₄ , ZrI ₄ , ZrOCl ₂ , ZrO (NO ₃ ) ₂ , ZrO (ClO ₄ ) ₂ , ZrO (SO ₄ ), Hf (OOCCH ₃ ) ₄ , Hf (CO ₃ ) ₂ , Hf (NO ₃ ) ₄ , Hf (SO ₄ ) ₂ , HfF ₄ , HfCl _{4 , HfBr 4, HfI 4, HfOCl} 2, V (CH 3 COCHCOCH 3) 3, VOSO 4, VOCl 3, VCl 3, VCl 4, VBr 3, Nb (CH 3 COCHCOCH 3) 5, Nb 2 (CO 3) 5 _{, Nb (NO 3) 5,} N _{2 (SO 4) 5, NbF} 5, NbCl 5, NbBr 5, NbI 5, Ta (OOCCH 3) 5, Ta 2 (CO 3) 5, Ta (NO 3) 5, Ta 2 (SO 4) 5, TaF _{5, TaCl 5, TaBr 5,} TaI 5, Cr (CH 3 COCHCOCH 3) 3, Cr (OOCCH 3) 3, Cr (OOCH) 2 OH, Cr (NO 3) 3, Cr (ClO 4) 3, CrPO 4 , Cr ₂ (SO ₄ ) ₃ , CrO ₂ Cl ₂ , CrF ₃ , CrCl ₃ , CrBr ₃ , CrI ₃ , MoOCl ₄ , MoCI ₃ , MoCI ₄ , MoCI ₅ , MoF ₆ , MoI ₂ , WCl ₄ , WCl ₆ , WF ₆ , WBr ₅ and the like.
Further, two or more of these salts may be used.
[0010]
The acid treatment, which may be performed prior to the contact with a specific salt (sometimes referred to as salt treatment) in the step (I), removes impurities on the surface and removes impurities such as Al, Fe, Mg, etc. having a crystal structure. Elute some or all of the ions.
The acid used in the acid treatment is selected from the above-mentioned inorganic or organic acids, preferably hydrochloric acid, sulfuric acid, nitric acid, acetic acid, and oxalic acid, and two or more thereof may be used simultaneously.
The conditions of the contact treatment with a salt and an acid are not particularly limited, but usually, the salt and the acid concentration are, for example, 0.1 to 30% by weight, respectively, in a solvent such as an aqueous solution, and the treatment temperature is from room temperature to use. At least a part of the substance constituting at least one compound selected from the group consisting of clay, clay minerals and ion-exchangeable layered compounds by selecting the conditions of the boiling point of the solvent and the treatment time of 5 minutes to 24 hours. Is preferably carried out under conditions that elute. Also, salts and acids are preferably used in aqueous solution.
In the present invention, the salt treatment is performed, but the shape may be controlled by pulverization or granulation before, during, or after the treatment. Further, another chemical treatment such as an alkali treatment or an organic substance treatment may be used in combination. Among the solid products thus obtained, those having a pore volume of not less than 0.1 cc / g, particularly preferably from 0.3 to 5 cc / g, having a radius of 20 ° or more as measured by a mercury intrusion method are preferable.
[0011]
Next, in step (II), the solid product obtained by the salt treatment is washed with water until the pH of the washing solution becomes 3 to 7. If the pH is out of the above range due to insufficient or excessive washing, the activity of the catalyst may decrease.
Washing is not particularly limited, but is usually performed by a known method such as decantation or water injection on filter paper. The temperature is also arbitrarily selected between room temperature and the boiling point. The salt-treated solid component thus washed is subsequently subjected to the drying step (III).
[0012]
The at least one compound selected from the group consisting of clay, clay minerals and ion-exchangeable layered compounds used in the present invention usually contains adsorbed water and interlayer water. In the present invention, the removal of the adsorbed water and the interlayer water is performed by drying in the step (III).
Here, the adsorbed water is water adsorbed on the surface of a clay, a clay mineral, or an ion-exchange layered compound particle or a crystal fracture surface, and the interlayer water is water existing between crystal layers. The method of heating and removing adsorbed water and interlayer water from clay, clay minerals or ion-exchange layered compounds is not particularly limited, but includes heating dehydration, heating dehydration under gas flow, heating dehydration under reduced pressure, and azeotropic dehydration with an organic solvent. Is used. The temperature at the time of heating is 100 ° C. or higher, preferably 150 ° C. or higher so that interlayer water does not remain. However, high-temperature conditions exceeding 800 ° C. that cause structural destruction are not preferable. Preferably it is 350 ° C. or lower. The heating time is 0.5 hour or more, preferably 1 hour or more and about 12 hours. At this time, the water content of the salt-treated solid product after dehydration and drying is 3% by weight or less when the water content is 0% by weight when dehydrated for 2 hours at a temperature of 200 ° C. and a pressure of 1 mmHg. , Preferably 1% by weight or less, and the lower limit must be 0% by weight or more.
[0013]
Finally, in step (IV), the solid product dried in step (III) is contact-treated with an organoaluminum compound to obtain a solid catalyst [A] for olefin polymerization.
The organoaluminum compound used here is a trialkylaluminum such as trimethylaluminum, triethylaluminum, tripropylaluminum, triisobutylaluminum, or a halogen or alkoxy-containing alkylaluminum such as diethylaluminum monochloride or diethylaluminummonomethoxy. In addition, aluminoxanes such as methylaluminoxane can also be used. Of these, trialkyl aluminum is particularly preferred.
[0014]
During or after the contact treatment, a polymer such as polyethylene or polypropylene, or a solid of an inorganic oxide such as silica or alumina may coexist or may be brought into contact.
The contact may be performed in an inert gas such as nitrogen or an inert hydrocarbon solvent such as pentane, hexane, heptane, toluene, or xylene. The contact temperature is between -20 ° C and the boiling point of the solvent, and preferably between room temperature and the boiling point of the solvent.
The amount of the organoaluminum compound to be used is 0.01 to 10,000 mmol, preferably 0.1 to 100 mmol, per 1 g of the solid product dried in the step (III).
The solid catalyst [A] thus obtained may be used without washing with an inert hydrocarbon solvent such as hexane, heptane, octane, decane, benzene, xylene, and toluene after the catalyst is produced. It may be used after washing.
[0015]
The organoaluminum compound of the component [B] used in combination with the solid catalyst [A] in the present invention is represented by the following general formula.
AlR _a X _3-a
(Wherein, R is a hydrocarbon group having 1 to 20 carbon atoms, X is hydrogen, a halogen, an alkoxy group, and a is 0 <a ≦ 3)
[0016]
Specifically, it is a trialkylaluminum such as trimethylaluminum, triethylaluminum, tripropylaluminum, triisobutylaluminum, or a halogen or alkoxy-containing alkylaluminum such as diethylaluminum monochloride or diethylaluminum monomethoxide. In addition, aluminoxanes such as methylaluminoxane can also be used. Of these, trialkyl aluminum is particularly preferred.
[0017]
In the present invention, it is preferable to use the component [B], and when the component [B] is used, the amount of the component [B] used is 0.001 to 100 mmol, preferably 0 to 1 mmol per 1 g of the solid catalyst [A]. 0.01 to 10 mmol.
The above-mentioned solid catalyst [A] can be used as it is obtained above, but before it is used for polymerization with an olefin, ethylene, propylene, 1-butene, 1-hexene, 1-octene, 4-methyl -1-Pentene, 3-methyl-1-butene, vinylcycloalkane, preliminarily contacted with an olefin such as styrene, polymerized, and optionally washed with the above inert hydrocarbon solvent as a catalyst. You can also.
This preliminary polymerization is preferably performed in an inert solvent under mild conditions, and is performed so as to produce 0.01 to 1000 g, preferably 0.1 to 100 g, of polymer per 1 g of the solid catalyst. desirable.
[0018]
Examples of the olefin used for the polymerization of the olefin of the present invention include ethylene, propylene, 1-butene, 1-hexene, 1-octene, 4-methyl-1-pentene, 3-methyl-1-butene, vinylcycloalkane, and styrene. Alternatively, derivatives thereof and the like can be mentioned. In addition to the homopolymerization of the above-mentioned olefins, the present invention can be suitably applied to random copolymerization using a mixture of two or more kinds of the above-mentioned olefins and block copolymerization using two or more kinds of olefins.
For the polymerization reaction, a known polymerization method using a Ziegler catalyst can be adopted, for example, in the presence or absence of a solvent such as an inert hydrocarbon such as butane, pentane, hexane, heptane, toluene and cyclohexane or a liquefied α-olefin. This is done in one or more stages below. The polymerization temperature is from -50 ° C to 250 ° C, and the polymerization pressure is not particularly limited, but preferably ranges from normal pressure to about 2000 kg · f / cm ² .
Further, hydrogen may be present as a molecular weight regulator in the polymerization system. Further, the polymerization may be performed in multiple stages by changing the polymerization temperature, the concentration of the molecular weight regulator, and the like.
[0019]
【Example】
Next, the present invention will be described more specifically with reference to examples. However, the present invention is not limited by these examples unless departing from the gist of the present invention.
The following catalyst synthesis step and polymerization step were all performed in a purified nitrogen atmosphere. The solvent used was dehydrated by molecular sieve MS-4A and then degassed by bubbling with purified nitrogen.
[0020]
In the examples, the melt index (MI) was measured at 190 ° C. under a load of 2.16 kg in accordance with ASTM D1238. At this time, 0.1% by weight of 2,6-di-t-butylparacresol was added to the polymer. Further, when the molecular weight was too high and the flowability of the molten polymer was extremely poor and it was difficult to measure MI, the weight average molecular weight (Mw; converted to polystyrene) was measured by GPC. The measurement of GPC was carried out at a measurement temperature of 145 ° C. using a 150 CV type device manufactured by Millipore, using ortho-dichlorobenzene as a solvent.
[0021]
Example 1
(1) Salt treatment and granulation of montmorillonite 8 kg of commercially available montmorillonite was ground by a vibrating ball mill, dispersed in 50 liters of demineralized water in which 10 kg of magnesium chloride was dissolved, and stirred at 80 ° C. for 1 hour. The obtained solid component was washed with water, dispersed in 56 liters of 8.2% aqueous hydrochloric acid solution, stirred at 90 ° C. for 2 hours, and washed with deionized water. The thus-treated water slurry of 4.6 kg of montmorillonite was adjusted to a solid concentration of 15.2%, and spray granulation was performed by a spray drier. The shape of the particles obtained by granulation was spherical. Next, 20 g of the granulated chemically treated montmorillonite was dispensed into a 1 liter flask, and then dispersed in 400 ml of desalted water in which 48 g of Cr (NO ₃ ) ₃ .9H ₂ O was dissolved, and then dispersed at 90 ° C. for 3 hours. Stirred. After the treatment, this solid component was washed with demineralized water until the pH of the washing solution reached 6, and dried to obtain a salt-treated montmorillonite.
[0022]
(2) Heat-dehydration treatment of salt-treated montmorillonite 10.0 g of the salt-treated montmorillonite obtained in (1) was placed in a 200 ml flask, and subjected to heat-dehydration treatment at 200 ° C. for 2 hours under a reduced pressure of 0.1 mmHg. A 1.3 g weight loss was observed in this dehydration treatment.
[0023]
(3) Synthesis of Catalyst [A] In a 100 ml flask, 3.0 g of the heat-dehydrated montmorillonite obtained in (2) was placed and dispersed in 20 ml of toluene to form a slurry. Then, 1.3 ml of triethylaluminum was added at room temperature with stirring. After contacting at room temperature for 1 hour, the supernatant was extracted and the solid portion was washed with toluene to obtain a catalyst [A].
[0024]
(4) Polymerization of Ethylene Into a 2 liter induction-stirring autoclave sufficiently purged with purified nitrogen, 1 liter of normal hexane, 0.15 mmol of triethylaluminum and 167.9 mg of the catalyst obtained in the above (3) were charged. Thereafter, after the temperature was raised to 90 ° C., ethylene was introduced to maintain the total pressure at 22.0 kg · f / cm ^2, and polymerization was carried out for 1 hour while stirring was continued. The polymerization was stopped by adding 10 ml of ethanol. The amount of the obtained ethylene polymer was 110 g. The Mw of this polymer was 2,976,000.
[0025]
Example 2
(1) Polymerization of ethylene 189.3 mg of the catalyst obtained in (3) of Example 1 was added, and hydrogen was added so that the gas composition in the autoclave became [H ₂ /ethylene]=45.3 mol%, followed by polymerization. Ethylene was polymerized in the same manner as in (4) of Example 1, except that the total pressure of the reaction system in the medium was 30.0 kg · f / cm ² . As a result, the obtained ethylene polymer was 91 g, and the MI was 4.42 g / 10 minutes.
[0026]
Example 3
(1) Ethylene-butene copolymer 222.9 mg of the catalyst obtained in (3) of Example 1, 740 ml of normal hexane, 160 ml of 1-butene, the polymerization temperature was changed to 70 ° C, and the reaction system during the polymerization was changed. The copolymerization of ethylene and 1-butene was carried out in the same manner as in (4) of Example 1 except that the total pressure was changed to 25.5 kg · f / cm ² . As a result, the obtained ethylene polymer was 84 g and Mw was 1,175,000.
[0027]
Example 4
(1) Salt treatment of synthetic mica 20 g of commercially available synthetic mica was placed in a 1-liter flask, and then dispersed in 400 ml of demineralized water in which 48 g of Cr (NO ₃ ) ₃ .9H ₂ O was dissolved. Stir for 3 hours. After the treatment, the solid product was washed with demineralized water until the pH of the washing solution reached 6, and dried to obtain a salt-treated synthetic mica.
(2) Heat-dehydration treatment of salt-treated synthetic mica 10.0 g of the chemically-treated synthetic mica obtained in (1) was placed in a 200 ml flask and subjected to heat-dehydration treatment at 200 ° C. for 2 hours under a reduced pressure of 0.1 mmHg. A 1.0 g weight loss was observed in this dehydration treatment.
[0028]
(3) Synthesis of Catalyst [A] 3.0 g of the synthetic mica heated and dehydrated obtained in (2) was placed in a 100 ml flask, and dispersed in 20 ml of toluene to form a slurry. Then, 1.3 ml of triethylaluminum was added at room temperature with stirring. After contacting at room temperature for 1 hour, the supernatant was extracted and the solid portion was washed with toluene to obtain a catalyst [A].
[0029]
(4) Polymerization of Ethylene In a 2 liter induction-stirring autoclave sufficiently purged with purified nitrogen, 1 liter of normal hexane, 0.15 mmol of triethylaluminum and 158.2 mg of the catalyst obtained in the above (3) were charged. Thereafter, after the temperature was raised to 90 ° C., ethylene was introduced to maintain the total pressure at 22.0 kg · f / cm ^2, and polymerization was carried out for 1 hour while stirring was continued. The polymerization was stopped by adding 10 ml of ethanol. The amount of the obtained ethylene polymer was 70 g.
[0030]
Comparative Example 1
(1) was collected 20g amount of silica salt treatment Davison Co. Silica 952 to a 1 liter flask, _{then, Cr (NO 3) 3 ·} 9H 2 O48g dispersed in demineralized water 400ml was dissolved, at 90 ° C. Stir for 3 hours. After the treatment, this solid product was washed with demineralized water until the pH of the washing solution reached 6, and dried to obtain salt-treated silica.
(2) Heat-dehydration treatment of salt-treated silica 10.0 g of the salt-treated silica obtained in (1) was placed in a 200 ml flask and subjected to heat-dehydration treatment at 200 ° C. for 2 hours under a reduced pressure of 0.1 mmHg. A 0.3 g weight loss was observed in this dehydration treatment.
[0031]
(3) Synthesis of catalyst [A] 3.0 g of the heat-dehydrated silica obtained in (2) was placed in a 100 ml flask, and dispersed in 20 ml of toluene to form a slurry. Then, 1.3 ml of triethylaluminum was added at room temperature with stirring. After contacting at room temperature for 1 hour, the supernatant was extracted and the solid portion was washed with toluene to obtain a catalyst [A].
[0032]
(4) Polymerization of Ethylene Into a 2 liter induction-stirring autoclave sufficiently purged with purified nitrogen, 1 liter of normal hexane, 0.15 mmol of triethylaluminum and 187.2 mg of the catalyst obtained in the above (3) were charged. Thereafter, after the temperature was raised to 90 ° C., ethylene was introduced to maintain the total pressure at 22.0 kg · f / cm ^2, and polymerization was carried out for 1 hour while stirring was continued. The polymerization was stopped by adding 10 ml of ethanol. The amount of the obtained ethylene polymer was 1 g.
[0033]
Example 5
(1) Salt treatment and granulation of montmorillonite 3.1 kg of commercially available montmorillonite was ground by a vibrating ball mill, dispersed in 17.7 liters of a 3.0% hydrochloric acid aqueous solution, and stirred at 90 ° C. for 3 hours. Then, after cooling to room temperature, this water slurry was spray granulated by using a spray drier. The shape of the particles obtained by granulation was spherical. Washed with water this granulated chemically treated montmorillonite in deionized water, and then, the process of montmorillonite 20g aliquoted into a 1 liter flask, _{then, Zr (SO 4) 2 ·} 4H 2 Demineralized water 400ml of O20g was dissolved And stirred at 90 ° C. for 3 hours. After the treatment, this solid product was washed with demineralized water until the pH of the washing solution reached 6, and dried to obtain a salt-treated montmorillonite.
[0034]
(2) Heat-dehydration treatment of salt-treated montmorillonite 10.0 g of the salt-treated montmorillonite obtained in (1) was placed in a 200 ml flask, and subjected to heat-dehydration treatment at 200 ° C. for 2 hours under a reduced pressure of 0.1 mmHg. A 1.2 g weight loss was observed in this dehydration treatment.
[0035]
(3) Synthesis of Catalyst [A] In a 100 ml flask, 3.0 g of the heat-dehydrated montmorillonite obtained in (2) was placed and dispersed in 20 ml of toluene to form a slurry. Then, 1.3 ml of triethylaluminum was added at room temperature with stirring. After contacting at room temperature for 1 hour, the supernatant was extracted and the solid portion was washed with toluene to obtain a catalyst [A].
[0036]
(4) Polymerization of ethylene Into a 2 liter induction-stirring autoclave sufficiently purged with purified nitrogen, 1 liter of normal hexane, 0.15 mmol of triethylaluminum, and 184.0 mg of the catalyst obtained in the above (3) were charged. Thereafter, after the temperature was raised to 90 ° C., ethylene was introduced to maintain the total pressure at 22.0 kg · f / cm ^2, and polymerization was carried out for 1 hour while stirring was continued. The polymerization was stopped by adding 10 ml of ethanol. The obtained ethylene polymer was 12 g.
[0037]
Example 6
(1) Salt treatment of montmorillonite 3.1 kg of commercially available montmorillonite was ground by a vibrating ball mill, dispersed in 17.7 liters of a 3.0% hydrochloric acid aqueous solution, and stirred at 90 ° C. for 3 hours. Then, it cooled to room temperature and washed with demineralized water. Next, 20 g of the treated montmorillonite was dispensed into a 1-liter flask, and then dispersed in 400 ml of demineralized water in which 20 g of VCl ₃ was dissolved, followed by stirring at 90 ° C. for 3 hours. After the treatment, this solid component was washed with demineralized water until the pH of the washing solution reached 6, and dried to obtain a salt-treated montmorillonite.
[0038]
(2) Heat-dehydration treatment of salt-treated montmorillonite 10.0 g of the salt-treated montmorillonite obtained in (1) was placed in a 200 ml flask, and subjected to heat-dehydration treatment at 200 ° C. for 2 hours under a reduced pressure of 0.1 mmHg. A weight loss of 1.4 g was recognized by this dehydration treatment.
[0039]
(3) Synthesis of Catalyst [A] In a 100 ml flask, 3.0 g of the heat-dehydrated montmorillonite obtained in (2) was placed and dispersed in 20 ml of toluene to form a slurry. Then, 1.3 ml of triethylaluminum was added at room temperature with stirring. After contacting at room temperature for 1 hour, the supernatant was extracted and the solid portion was washed with toluene to obtain a catalyst [A].
[0040]
(4) Polymerization of Ethylene In a 2 liter induction-stirring autoclave sufficiently purged with purified nitrogen, 1 liter of normal hexane, 0.15 mmol of triethylaluminum and 173.4 mg of the catalyst obtained in the above (3) were charged. Thereafter, after the temperature was raised to 90 ° C., ethylene was introduced to maintain the total pressure at 22.0 kg · f / cm ^2, and polymerization was carried out for 1 hour while stirring was continued. The polymerization was stopped by adding 10 ml of ethanol. The amount of the obtained ethylene polymer was 3 g.
[0041]
【The invention's effect】
According to the present invention, a novel catalyst suitable for olefin polymerization and a method for polymerizing olefin using the catalyst are provided.

Claims (3)

Olefin polymerization catalyst [A] produced by sequentially performing the following steps (I) to (IV),
(I) at least one compound selected from the group consisting of clays, clay minerals, and ion-exchangeable layered compounds, containing at least one atom selected from the group consisting of transition metal atoms of Groups 4 to 6 of the periodic table; Contacting a salt soluble in an aqueous or acidic aqueous solution comprising a cation and at least one anion selected from the group consisting of a halogen atom, an anion of an inorganic acid and an organic acid, to obtain a solid product ,
(II) washing the solid product with water until the washing solution has a pH of 3 to 7;
(III) drying the washed solid product;
(IV) A step of contacting the dried solid product with an organoaluminum compound to obtain a catalyst [A]. A method for producing an olefin polymer, comprising polymerizing an olefin in the presence of the olefin polymerization catalyst [A] according to claim 1. A method for producing an olefin polymer, comprising polymerizing an olefin in the presence of the olefin polymerization catalyst [A] according to claim 1 and an organoaluminum compound [B].