JP4083457B2 - Propylene polymerization catalyst and propylene polymerization method - Google Patents

Description

【００４４】
【発明の効果】
本発明を使用すれば、高融点なプロピレン系重合体が得られる。特にプロピレンの単独重合体に有効に適用される。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a catalyst for propylene polymerization and a method for polymerizing propylene using the catalyst. The propylene polymerization in the present invention includes propylene homopolymerization, but also includes copolymerization of propylene and other comonomers.
[0002]
[Prior art]
The use of layered silicates as catalyst components for olefin polymerization is known. It is disclosed in, for example, JP-A-5-295022 and JP-A-5-301917 that it functions as a catalyst component for olefin polymerization when combined with a Group 4-6 transition metal compound. In these inventions, it is stated that the role of the layered silicate has not only a function as a catalyst support but also a function as a promoter for causing the transition metal compound to exhibit polymerization activity.
[0003]
For these purposes, various proposals have been made regarding a method for treating a layered silicate as means for improving the catalytic activity and improving the particle properties of the polymer. For example, acid treatment or salt treatment is performed on a layered silicate (JP-A-7-228621, JP-A-7-309906, JP-A-7-309907, JP-A-7-228621, JP-A-8-127613, JP-A-10-168109). Etc.), washing after laminating the layered silicate followed by acid treatment (Japanese Patent Laid-Open No. 7-228621), or granulating and washing after laminating the layered silicate after acid treatment (Japanese Patent Laid-Open No. 9-136163, Japanese Patent Laid-Open No. 9-194517, etc.), and the treatment of layered silicates in the presence of acids and salts (Japanese Patent Laid-Open No. 10-168110) have been proposed.
Further, a technique for obtaining a high molecular weight polymer by supporting a metallocene compound on a layered silicate and then adding a nitrogen or phosphorus-containing compound is also known (Japanese Patent Laid-Open No. 11-140111).
[0004]
However, little consideration has been given to controlling the melting point of the polymer by controlling the properties of the layered silicate.
[0005]
[Problems to be solved by the invention]
An object of the present invention is to provide a propylene polymerization catalyst in which the polymer obtained by polymerization has a high melting point by controlling the properties of the layered silicate.
[0006]
[Means for Solving the Problems]
As a result of intensive studies on the above problems, the present inventors have modified a layered silicate with a specific compound, and combined it with a Group 4-6 transition metal compound to provide a catalyst having a high melting point of the polymer obtained by polymerization. I found.
That is, the present invention relates to a propylene polymerization catalyst comprising the following components [A], [B], [C] and a component [D] used as necessary.
Component [A]: Group 4 transition metal compound
Component [B]: chemically treated layered silicate
Component [C]: Substituted pyridine compound
Component [D]: Organoaluminum compound
[0007]
DETAILED DESCRIPTION OF THE INVENTION
One of the roles of the layered silicate in the polymerization catalyst is to activate the Group 4-6 transition metal compound. Upon activation, the Group 4-6 transition metal compound becomes a cation, which is considered to be a central part that acts as a polymerization catalyst. Another role of the layered silicate is to provide an atmosphere in which this cation is stably present.
The activation ability of the layered silicate influences the polymerization activity of the catalyst, and the cation stabilization ability is considered to determine the nature of the active site. Therefore, it is considered that not only the polymerization activity but also the physical properties of the polymer obtained can be controlled by controlling the properties of the layered silicate.
The point of the present invention is to improve the melting point of the polymer by modifying the layered silicate with a substituted pyridine compound to control the properties.
[0008]
(1) Layered silicate as a raw material for component [B]
The layered silicate has a Si tetrahedron and an Al or Mg octahedron as the smallest structural unit, and has a crystal structure in which planes composed of ionic bonds and other weak bonds are stacked in parallel to each other, and ions can be exchanged. Is. Most layered silicates are naturally produced mainly as the main component of clay minerals, but are not limited to natural ones, and may be artificial synthetic products.
[0009]
Specific examples of the layered silicate are known layered silicates described in, for example, Haruo Shiramizu “Clay Mineralogy” Asakura Shoten (1995), etc., and have a 1: 1 type structure or a 2: 1 type structure. There are things you have. The 1: 1 type structure is a structure based on the stacking of the 1: 1 layer structure in which one layer of tetrahedron sheet and one layer of octahedron sheet are combined, and the 2: 1 type structure is two layers. The structure based on the stacking | stacking of 2: 1 layer structure in which the tetrahedron sheet | seat pinched | interposed the octahedral sheet | seat of 1 layer is shown.
[0010]
Specific examples of layered silicates in which the 1: 1 layer is the main constituent layer include kaolins such as dickite, nacrite, kaolinite, anoxite, metahalloysite, and halloysite, serpentine such as chrysotile, risardite, and antigolite. Stone group and the like. Specific examples of layered silicates in which the 2: 1 layer is the main constituent layer include montmorillonite, sauconite, beidellite, nontronite, saponite, hectorite, stemite and other smectites, vermiculite and other vermiculites, mica, Examples include mica such as illite, sericite, sea chlorite, attapulgite, sepiolite, palygorskite, bentonite, pyrophyllite, talc, chlorite. These may form a mixed layer. In these, the layered silicate which a main component has a 2: 1 type structure is preferable. More preferably, the main component is a smectite group, and still more preferably, the main component is montmorillonite.
[0011]
(2) Chemical treatment of layered silicate
In the present invention, a layered silicate subjected to chemical treatment is used as component [B]. Here, the chemical treatment may be any of a surface treatment for removing impurities adhering to the surface, a treatment that affects the structure of the clay, and a treatment that changes the characteristics of the pore distribution. Specifically, acid treatment, alkali treatment, salt treatment, organic matter treatment and the like can be mentioned. Of these, acid treatment, salt treatment and a combination treatment thereof are preferable.
[0012]
In addition to removing impurities on the surface, the acid treatment can elute some or all of cations such as Al, Fe, and Mg having a crystal structure. The acid used in the acid treatment is preferably selected from hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, acetic acid, and oxalic acid. Usually, it is used in the form of an acid aqueous solution. The acid used for the treatment may be a mixture of two or more.
General treatment conditions with an acid can be arbitrarily selected from an acid concentration of 0.1 to 50% by weight, a treatment temperature of room temperature to a boiling point, and a treatment time of 5 minutes to 24 hours. It is preferable to carry out under the condition that at least a part of the substance constituting at least one compound selected from the group consisting of layered silicates is eluted.
[0013]
Salt treatment refers to treatment performed for the purpose of exchanging cations in the layered silicate. The treatment conditions with the salt are not particularly limited, but the salt is 0.1 to 50% by weight, the treatment temperature is from room temperature to boiling point, and the treatment time is from 5 minutes to 24 hours. It is preferable to carry out under conditions that elute at least a part of the constituent substances. Further, the salt can be used in an organic solvent such as toluene, n-heptane, ethanol, or the like as long as the salt is liquid at the treatment temperature, but it is preferably used as an aqueous solution. However, depending on the type of salt, there may be an effect similar to acid treatment.
Two or more salts and acids may be used. In the case of combining the salt treatment and the acid treatment, there are a method of performing the acid treatment after the salt treatment, a method of performing the salt treatment after the acid treatment, and a method of simultaneously performing the salt treatment and the acid treatment.
[0014]
As chemical treatment with other compounds, LiOH, NaOH, KOH, Mg (OH)₂, Ca (OH)₂, Sr (OH)₂, Ba (OH)₂  There are alkali treatments such as trimethylammonium and triethylammonium. Examples of the anion that constitutes the organic treatment agent include hexafluorophosphate, tetrafluoroborate, tetraphenylborate, and the like in addition to the anions exemplified as the anion that constitutes the salt treatment agent. It is not limited.
[0015]
After carrying out the chemical treatment, it is possible to remove excess treatment agent and ions eluted by the treatment, which is a preferable method. At this time, generally, a liquid such as water or an organic solvent is used. Although drying is performed after dehydration, in general, the drying temperature can be 100 to 800 ° C., and a high temperature condition (for example, 800 ° C. or higher depending on the heating time) that causes structural destruction is not preferable.
[0016]
Since the silicate treated by the method of the present invention changes its properties depending on the drying temperature even if it is not structurally destroyed, it is preferable to change the drying temperature according to the application. The drying time is usually 1 minute to 24 hours, preferably 5 minutes to 4 hours, and the atmosphere is preferably dry air, dry nitrogen, dry argon, or under reduced pressure. It does not specifically limit regarding a drying method, It can implement by various methods.
The silicate obtained by the chemical treatment according to the present invention includes not only a layered silicate having ion exchange properties as in the case of the raw layered silicate, but also physical and chemical properties by adding the treatment. Also included are silicates that have changed to no longer have ion exchange or layer structure.
[0017]
(3) Component [A]: Group 4 transition metal compound
Component [A] used in the present invention is a transition metal compound of Group 4 of the periodic table (refers to the periodic table according to IUPAC inorganic chemical nomenclature (1990)). Examples thereof include transition metal halides, transition metal metallocene compounds, transition metal bisamide or bisalkoxide compounds, and transition metal phenoxyimine compounds.
Particularly preferred are Group 4 transition metal compounds having at least one conjugated five-membered ring ligand. Preferred as such transition metal compounds are compounds represented by the following general formulas (I) to (III). These compounds are used alone or as a mixture of two or more.
[0018]
(C_FiveH_5-aR¹ _a) (C_FiveH_5-bR² _b) MXY (I)
Q (C_FiveH_5-cR¹ _c) (C_FiveH_5-dR² _d) MXY (II)
Q '(C_FiveH_5-eR² _e) ZMXY (III)
[0019]
Here, Q is a binding group that bridges two conjugated five-membered ring ligands, Q ′ is a binding group that bridges the conjugated five-membered ring ligand and the Z group, and M is the fourth transition of the periodic table. In the metal, X and Y are each independently hydrogen, a halogen group, a hydrocarbon group having 1 to 20 carbon atoms, an oxygen-containing hydrocarbon group having 1 to 20 carbon atoms, or a nitrogen-containing hydrocarbon having 1 to 20 carbon atoms. Group, phosphorus-containing hydrocarbon group having 1 to 20 carbon atoms or silicon-containing hydrocarbon group having 1 to 20 carbon atoms, Z is oxygen, sulfur, alkoxy group having 1 to 20 carbon atoms, silicon containing 1 to 40 carbon atoms A hydrocarbon group, a nitrogen-containing hydrocarbon group having 1 to 40 carbon atoms or a phosphorus-containing hydrocarbon group having 1 to 40 carbon atoms is shown. M is particularly preferably a Group 4 transition metal such as Ti, Zr, or Hf.
[0020]
R¹And R²Are each independently a hydrocarbon group having 1 to 20 carbon atoms, a halogen group, a halogen-containing hydrocarbon group having 1 to 20 carbon atoms, an alkoxy group, an aryloxy group, a silicon-containing hydrocarbon group, a phosphorus-containing hydrocarbon group, A nitrogen-containing hydrocarbon group or a boron-containing hydrocarbon group is shown. Two adjacent Rs¹Or 2 R²May be bonded to each other to form a C4-C10 ring. a, b, c, d and e are integers satisfying 0 ≦ a ≦ 5, 0 ≦ b ≦ 5, 0 ≦ c ≦ 4, 0 ≦ d ≦ 4 and 0 ≦ e ≦ 4, respectively. )
[0021]
Specific examples of the binding group Q that bridges between two conjugated five-membered ring ligands and the binding group Q ′ that bridges the conjugated five-membered ring ligand and Z group are as follows. Is mentioned. Methylene group, alkylene group such as ethylene group, ethylidene group, propylidene group, isopropylidene group, phenylmethylidene group, alkylidene group such as diphenylmethylidene group, dimethylsilylene group, diethylsilylene group, dipropylsilylene group, diphenyl Silicon-containing crosslinking groups such as silylene group, methylethylsilylene group, methylphenylsilylene group, methyl-t-butylsilylene group, disilylene group, tetramethyldisylylene group, germanium-containing crosslinking group, alkylphosphine, amine, etc. . Of these, an alkylene group, an alkylidene group, and a silicon-containing crosslinking group are particularly preferably used.
[0022]
Examples of the compound represented by the general formula (I) include
(1) bis (tetrahydroindenyl) zirconium dichloride,
(2) bis (2-methylindenyl) zirconium dichloride,
(3) bis (2-ethyl-4-phenyl-4H-azurenyl) hafnium dichloride,
(4) bis (2-ethyl-4- (p-chlorophenyl) -4H-azurenyl) zirconium dichloride,
Examples of the compound represented by the general formula (II) include
(5) Dimethylsilylenebis {1- (2-methyl-4-phenylindenyl)} zirconium dichloride,
(6) Dimethylsilylenebis {1- (2-ethylbenzoindenyl)} zirconium dichloride,
(7) Dimethylsilylenebis [1- {2-methyl-4- (4-chlorophenyl) -4H-azulenyl}] zirconium dichloride,
(8) Dimethylsilylenebis [1- {2-methyl-4- (4-fluorophenyl) -4H-azulenyl}] zirconium dichloride,
Examples of the compound represented by the general formula (III) include
(1) Dimethylsilanediyl (tetramethylcyclopentadienyl) (t-butylamido) titanium dichloride,
(2) Dimethylsilanediyl (tetramethylcyclopentadienyl) (cyclododecylamide) titanium dichloride,
(3) Dimethylsilanediyl (tetramethylcyclopentadienyl) (trimethylsilylamide) titanium dichloride,
(4) Dimethylsilanediyl (tetramethylcyclopentadienyl) (t-butylamido) titanium dimethyl,
(5) Dimethylsilanediyl (2-methylindenyl) (t-butylamido) titanium dichloride,
(6) Dimethylsilanediyl (fluorenyl) (t-butylamido) titanium dichloride,
(7) Dimethylsilanediyl (3,6-diisopropylfluorenyl) (t-butylamide) titanium dichloride and the like.
[0023]
(4) Component [C]: Substituted pyridine compound
The substituted pyridine compound used in the present invention has at least one substituent on the pyridine skeleton. The substituent is preferably an alkyl group, and the number of substituents is preferably 2 to 3. For example, 2-methylpyridine, 3-methylpyridine, 4-methylpyridine, 2,6-dimethylpyridine, 2,5-dimethylpyridine, 2,4-dimethylpyridine, 2,3-dimethylpyridine, 2,3,4-trimethylpyridine, 2,3,5-trimethylpyridine, 2,3,Examples include 6-trimethylpyridine. The amount of component [C] used is usually 1 to 10,000 per gram of component [B].μmol, preferably 5 to 1000μmol, particularly preferably 30 to 500μmol. If the amount is less than the above range, the effect of improving the melting point is small, and if too large, the polymerization activity is adversely affected.
[0024]
(5) Component [D]: Organoaluminum compound
The propylene polymerization catalyst of the present invention comprises the above-described components [A], [B], [C] and a component [D] used as necessary: an organoaluminum compound.
Such an organoaluminum compound has a general formula: (AlRnX_3-n) M. In formula, R represents a C1-C20 alkyl group, X represents a halogen, hydrogen, an alkoxy group, or an amino group, n represents 1-3, m represents the integer of 1-2, respectively. The organoaluminum compounds can be used alone or in combination.
[0025]
Specific examples of the organoaluminum compound include trimethylaluminum, triethylaluminum, trinormalpropylaluminum, trinormalbutylaluminum, triisobutylaluminum, trinormalhexylaluminum, trinormaloctylaluminum, trinormaldecylaluminum, diethylaluminum chloride, diethylaluminum. Examples thereof include sesquichloride, diethylaluminum hydride, diethylaluminum ethoxide, diethylaluminum dimethylamide, diisobutylaluminum hydride, and diisobutylaluminum chloride. Of these, trialkylaluminum and alkylaluminum hydride with m = 1 and n = 3 are preferable. More preferably, R is a trialkylaluminum having 1 to 8 carbon atoms.
[0026]
(6) Preparation of propylene polymerization catalyst
a: Prepolymerization
The catalyst of the present invention is prepared by bringing the component [A], the component [B], the component [C], and the component [D] used as necessary into contact with each other inside or outside the polymerization vessel. Preferably, the contacting of each component can be carried out in the presence of a small amount of olefin and prepolymerized. Olefin means a hydrocarbon containing at least one carbon-carbon double bond, and examples include ethylene, propylene, 1-butene, 1-hexene, 3-methylbutene-1, styrene, divinylbenzene, etc. Rather, a mixture of these and other olefins may be used. An olefin having 3 or more carbon atoms is preferable. The prepolymerization is usually carried out at a prepolymerization ratio (a value obtained by dividing the amount of the prepolymerized polymer by the amount of the solid catalyst) of usually 0.1 to 100, preferably about 1 to 10.
[0027]
b: Use amount of each component
Although the usage-amount of said component [A] does not have a restriction | limiting in particular, It is 0.1-10000 micromol per 1 g of component [B], Preferably it is 1-1000 micromol, More preferably, it is 5-100 micromol.
Although there is no restriction | limiting in particular in the usage-amount of component [D], It is 0-100 mmol per 1 g of component [B], Preferably it is 0.1-10 mmol, More preferably, it is 1-5 mmol.
[0028]
c: Order and method of contacting each component
The order in which the component [A], the component [B], the component [C], and the component [D] are contacted is arbitrary. These three to four components may be contacted at the same time, or two types may be sequentially contacted. Preferably, the component [A] is contacted after the components [B] and [C] are contacted. Moreover, you may combine 2 or more types of components [A], [B], [C], and [D], respectively. In this case, different types of components [A], [B], [C], and [D] may be contacted simultaneously or sequentially. Moreover, you may wash | clean with a solvent etc. after a contact.
The contacting method is not particularly limited, but it is preferable to contact in a solvent so that the contact can be made uniformly. Examples of the solvent include aliphatic saturated hydrocarbons, aromatic hydrocarbons, aliphatic unsaturated hydrocarbons, halides thereof, and prepolymerized monomers.
[0029]
d: Drying of catalyst
The catalyst for propylene polymerization of the present invention may be dried after preliminary polymerization. There are no particular restrictions on the drying method, but examples include vacuum drying, heat drying, and drying by circulating a drying gas. These methods may be used alone or in combination of two or more methods. Also good. In the drying step, the catalyst may be stirred, vibrated, fluidized, or allowed to stand. As for the degree of drying, it is desirable that the residual solvent amount is 10% by weight or less, preferably 5% by weight or less, based on the total weight so that the catalyst can be handled easily when powdered.
[0030]
e: Polymerization (main polymerization)
The propylene polymerization in the present invention includes propylene homopolymerization, but also includes copolymerization of propylene and other comonomers. Polymerization carried out using a polymerization catalyst comprising the component [A], the component [B], the component [C], and the component [D] that is used as necessary is carried out by mixing propylene alone or propylene and another comonomer. This is done by contacting them. In the case of copolymerization, the amount ratio of each monomer in the reaction system does not need to be constant over time, and it is convenient to supply each monomer at a constant mixing ratio. It is also possible to change it. Also, any of the monomers can be added in portions in consideration of the copolymerization reaction ratio.
[0031]
In the case of copolymerization, the type of comonomer used preferably has about 2 to 20 carbon atoms. Specifically, ethylene, propylene, 1-butene, 1-hexene, 1-octene, and the like are selected and used. Can do. The catalyst of the present invention is particularly effective when used in the production of a propylene homopolymer or a copolymer of propylene and another monomer. Among them, it is advantageous for producing a random copolymer of propylene and ethylene. In particular, it is advantageous when producing a propylene having a content of 90 to 100 mol%, preferably 98 to 100 mol%.
[0032]
As the polymerization mode, any mode can be adopted as long as the catalyst component and each monomer come into contact efficiently. Specifically, a slurry method using an inert solvent, a slurry method using substantially no inert solvent and propylene as a solvent, a solution polymerization method, or a gas that keeps each monomer in a gaseous state without using a liquid solvent. Phase method can be adopted. Further, a method of performing continuous polymerization, batch polymerization, or multistage polymerization is also applied.
[0033]
In the case of slurry polymerization, a saturated aliphatic or aromatic hydrocarbon such as hexane, heptane, pentane, cyclohexane, benzene, toluene, or the like is used alone or as a polymerization solvent. The polymerization temperature is 0 to 150 ° C., and hydrogen can be used as an auxiliary molecular weight regulator. The polymerization pressure is 0 to 2000 kg / cm.²G, preferably 0-60 kg / cm²G is appropriate.
[0034]
【Example】
EXAMPLES Next, although an Example demonstrates this invention concretely, this invention will not be restrict | limited by these Examples, unless it deviates from the summary.
In addition, each measuring method in a present Example is as follows.
(1) Melt flow rate (MFR): According to JIS-K-6758
(2) Crystallization temperature (Tc): Using a differential scanning calorimeter (DSC6200, manufactured by Seiko Instruments Inc.), a sample piece made into a sheet is packed in a 5 mg aluminum pan and once heated from room temperature to 200 ° C, the heating rate is 100 ° C / The temperature was raised in minutes, held for 5 minutes, and then obtained as the maximum crystallization peak temperature (° C.) when the temperature was lowered to 40 ° C. at 10 ° C./min for crystallization.
(3) Melting point (Tm): Using a differential scanning calorimeter (DSC6200, manufactured by Seiko Instruments Inc.), a sample piece made into a sheet is packed in a 5 mg aluminum pan and once heated from room temperature to 200 ° C. at a heating rate of 100 ° C./min. After raising the temperature and holding for 5 minutes, the temperature is lowered to 40 ° C. at 10 ° C./min to crystallize, and then calculated as the maximum melting peak temperature (° C.) when the temperature is raised to 200 ° C. at 10 ° C./min. It was.
[0035]
[Example 1]
(1-1) Chemical treatment of layered silicate
In a separable flask, 96% sulfuric acid (1500 g) was added to 2260 g of distilled water, and then 600 g of montmorillonite (Mizusawa Chemical Benclay SL: average particle size 27 μm) was added as a layered silicate. The slurry was heated to 90 ° C. over 1 hour at 0.5 ° C./minute, and reacted at 90 ° C. for 390 minutes. The reaction slurry was cooled to room temperature in 1 hour and washed to pH 3 with distilled water. The resulting solid was preliminarily dried at 130 ° C. for 2 days under a nitrogen stream, and then coarse particles of 53 μm or more were removed, and further dried at 215 ° C. under a nitrogen stream under a rotary kiln condition for 295 g of chemically treated smectite. Got. The composition of this chemically treated smectite is Al: 4.7 wt%, Si: 41.7 wt%, Mg: 0.70 wt%, Fe: 1.1 wt%, Na <0.2 wt%, Al /Si=0.117 [mol / mol].
[0036]
(1-2) Preparation of catalyst and prepolymerization
Into a three-necked flask (volume: 1 L), 20 g of the chemically treated smectite obtained above was put, and heptane (116 mL) containing 3% by weight of toluene was added to form a slurry, to which triethylaluminum (50 mmol: concentration 68 mg / mL) was added. 84 mL) of heptane solution was added and stirred for 1 hour, then washed with heptane to 1/1000, and heptane containing 3% by weight of toluene was added so that the total volume became 200 mL. To this, 8 ml of a 0.2M toluene solution of 2,6-dimethylpyridine as a substituted pyridine compound and 80 μmol per 1 g of layered silicate were added and stirred for 10 minutes.
In another flask (volume: 200 mL), (dimethylsilylene bis (2-methyl-4-phenylindenyl) zirconium dichloride (0.3 mmol) was added to heptane (87 mL) containing 3% by weight of toluene to prepare a slurry. Then, triisobutylaluminum (0.6 mmol: 0.85 mL of a 140 mg / mL concentration of heptane solution) was added, and the mixture was stirred for 60 minutes at room temperature to react with the above 2,6-dimethylpyridine. The mixture was added to the 3 L flask containing the chemically treated smectite and stirred at room temperature for 60 minutes, after which 213 mL of heptane containing 3 wt% toluene was added, and this slurry was introduced into a 1 L autoclave.
After the internal temperature of the autoclave was set to 40 ° C., propylene was fed at a rate of 20 g / hour and prepolymerization was performed while maintaining the temperature at 40 ° C. for 2 hours. Thereafter, propylene feed was stopped and residual polymerization was performed at 50 ° C. for 2 hours. The supernatant of the resulting catalyst slurry was removed by decantation, and triisobutylaluminum (12 mmol: 17 mL of a heptane solution having a concentration of 140 mg / mL) was added to the remaining portion as a deactivation inhibitor and stirred for 10 minutes. This solid was dried under reduced pressure for 2 hours to obtain 65.0 g of a dry prepolymerized catalyst. The prepolymerization ratio (a value obtained by dividing the amount of the prepolymerized polymer by the amount of the solid catalyst) was 2.25.
[0037]
(1-3) Propylene polymerization
To a 3 L autoclave, 2.86 mL of a heptane solution of triisobutylaluminum (140 mg / mL) was added, 102 mL of hydrogen (volume in a standard state) and 750 g of liquid propylene were introduced, and then the temperature was raised to 70 ° C. Thereafter, 100 mg of the above prepolymerized catalyst by weight excluding the prepolymerized polymer was pumped to the polymerization tank with high-pressure argon and polymerized at 70 ° C. for 1 hour. The obtained polymer had an MFR of 0.49 g / 10 min, a melting point of 149.7 ° C., and a crystallization temperature of 112.6 ° C.
The results are shown in Table 1, including the following examples. The abbreviations in Table 1 mean the following.
Indenyl Zr: Dimethylsilylenebis (2-methyl-4-phenylindenyl) zirconium dichloride
Azulenyl Zr: dimethylsilylenebis (2-methyl-4- (p-chlorophenyl) dihydroazurenyl) zirconium dichloride
TEA: Triethylaluminum
TIBA: Triisobutylaluminum
[0038]
[Example 2]
(2-1) Prepolymerization
A prepolymerized catalyst was obtained in the same manner as in Example (1-2) except that the amount of a 0.2M toluene solution of 2,6-dimethylpyridine, which is a substituted pyridine compound, was 20 ml and 200 μmol per 1 g of layered silicate. The prepolymerization ratio was 0.24.
(2-2) Propylene polymerization
Polymerization was conducted in the same manner as in Example (1-3) except that the prepolymerized catalyst was used. The obtained polymer had an MFR of 1.75 g / 10 min, a melting point of 149.7 ° C., and a crystallization temperature of 113.4 ° C.
[0039]
[Comparative Example 1]
(Ratio 1-1) Preliminary polymerization
A prepolymerized catalyst was obtained in the same manner as in Example (1-2) except that the amount of the substituted pyridine compound was zero. The prepolymerization ratio was 1.81.
(Ratio 1-2) Propylene polymerization
Polymerization was conducted in the same manner as in Example (1-3) except that 200 mg of the above prepolymerized catalyst (weight excluding the prepolymerized polymer) was used. The obtained polymer had an MFR of 0.50 g / 10 min, a melting point of 147.4 ° C., and a crystallization temperature of 111.1 ° C.
[0040]
[Example 3]
(3-1) Prepolymerization
Instead of dimethylsilylene bis (2-methyl-4-phenylindenyl) zirconium dichloride, dimethylsilylene bis (2-methyl-4- (p-chlorophenyl) dihydroazurenyl) zirconium dichloride is used, which is a substituted pyridine compound. A prepolymerized catalyst was obtained in the same manner as in Example (1-2) except that the amount of a 0.2M toluene solution of 2,6-dimethylpyridine was changed to 4 ml and 40 μmol per gram of layered silicate. The prepolymerization ratio was 0.61.
(3-2) Propylene polymerization
Polymerization was conducted in the same manner as in Example (1-3) except that the prepolymerized catalyst was used. The obtained polymer had an MFR of 2.62 g / 10 min, a melting point of 149.1 ° C., and a crystallization temperature of 111.1 ° C.
[0041]
[Example 4]
(4-1) Prepolymerization
A prepolymerized catalyst was obtained in the same manner as in Example (3-1) except that the amount of a 0.2M toluene solution of 2,6-dimethylpyridine, which is a substituted pyridine compound, was 8 ml and 80 μmol per gram of layered silicate. The prepolymerization ratio was 0.53.
(4-2) Propylene polymerization
Polymerization was conducted in the same manner as in Example (1-3) except that the prepolymerized catalyst was used. The obtained polymer had an MFR of 2.65 g / 10 min, a melting point of 149.4 ° C., and a crystallization temperature of 111.1 ° C.
[0042]
[Comparative Example 2]
(Ratio 2-1) Preliminary polymerization
A prepolymerized catalyst was obtained in the same manner as in Example (3-1) except that the amount of the substituted pyridine compound was zero. The prepolymerization ratio was 2.28.
(Ratio 1-2) Propylene polymerization
Polymerization was conducted in the same manner as in Example (1-3) except that the prepolymerized catalyst was used. The obtained polymer had an MFR of 1.97 g / 10 min, a melting point of 148.6 ° C., and a crystallization temperature of 111.0 ° C.
[0043]
[Table 1]

[0044]
【The invention's effect】
If this invention is used, a high melting point propylene polymer will be obtained. In particular, it is effectively applied to a propylene homopolymer.

Claims (9)

A propylene polymerization catalyst comprising the following components [A], [B], [C] and a component [D] used as necessary.
Component [A]: Group 4 transition metal compound component [B]: Chemically treated layered silicate component [C]: Substituted pyridine compound component [D]: Organoaluminum compound The catalyst for propylene polymerization according to claim 1, wherein the chemical treatment of component [B] is an acid treatment. The catalyst for propylene polymerization according to any one of claims 1 to 2, wherein the layered silicate of the component [B] is smectite. The catalyst for propylene polymerization according to any one of claims 1 to 3, wherein the layered silicate of the component [B] is montmorillonite. The catalyst for propylene polymerization according to any one of claims 1 to 4, wherein the component [C] is a substituted pyridine compound having lower alkyl groups at the 2-position and the 6-position. 6. The propylene polymerization catalyst according to claim 1, wherein the amount of the component [C] used is 5 to 1000 μmol per 1 g of the component [B]. The catalyst for propylene polymerization according to any one of claims 1 to 6, wherein the component [B] and the component [C] are contacted in advance, and then the component [A] is contacted with the contact product. Component [A] has at least 1 indenyl ligand, The catalyst for propylene polymerization of any one of Claims 1-7 characterized by the above-mentioned. A method for polymerizing propylene using the catalyst for propylene polymerization according to any one of claims 1 to 8.